modifying time it takes for summoned allies to appear
 

B38 "take a Concentrate maneuver and roll against frequency of appearance. On a success, your Ally appears nearby"

I thought that might be instant until I read pg 41 of Powers:

The GM determines how long it takes summoned beings to appear.
This can vary with the circumstances:
fire elementals might appear instantly in a volcano but not at all at sea,
animals might need to reach the summoner on foot,
and so on.
This variability makes most modifiers that affect time requirements inappropriate.

Is there any alternate options for getting a fixed time until arrival? This makes it sound like "your allies already exist somewhere and you can just call them to travel to you at whatever speed they are capable of".

Is there something more like a "create out of thin air in a fixed amount of time" alternate option to this, to which you could apply modifiers that affect time requirements?

P95 (Alternatives to Illusion) recommends this as one option to "conjure material creations" in which case travel time wouldn't necessarily matter if you were to say, create a raven ally out of thin air, though in the case of a fire elemental I could see how it might go faster making them if raw materials like lava were available or you weren't underwater and damaging fire as you created it.

Even though P41 mentions an option to "bring forth new allies each time", I'm guessing this is probably meant to be a fixed kind of ally. Like you'd have "Ally: Goblin Warrior" but each time you summoned a goblin it'd be a different goblin warrior with similar capabilities but no memory or friendship with you.

I figure it's not that versatile since P64 mentions "Only Allies with Minion and Summonable" as an optional limitation for Modular Abilities, which sounds like what you're supposed to do if you want to change what type of things you're able to summon by moving character points around?

P29 mentions

Talent doesn’t normally modify reaction rolls, either, but the GM might make exceptions for entities directly conjured by the power (such as Allies with the Summonable enhancement)

Sort of seems to contradict P41's "Powering Up" note:

Talent never affects appearance rolls but does add to the summoner’s rolls to influence his Allies and his Allies’ reactions toward him.

So I figure that you have a generic "non-conjured summon" and a "conjured summon"

Non-conjured would have variable time until appearance based on distance (how near is the forest? how near is the volcano?) and the appearance rolls do not benefit from talent...

Conjured would have fixed time and appearance rolls DO benefit from talents.

The 2nd one sounds better unless it had a medium basic time compared to a variable (short to long) time for non-conjured summons.

For example if Raven Ally (Summonable: Conjured) took 10 seconds to make a raven out of thing air, then Raven Ally (Summonable: Called) might take 1 second if there is a raven in the immediate area (instantly helps you) but it might take 100 seconds if the nearest raven nest is 2400 yards away (ravens fly about 50mph or 24 yards per second)

The other problem with reusability is that with "called" summons you could deplete the local raven populations sending them to fight eagles, while "conjured" summons would have no concern (with "Constantly" Frequency of Appearance, you can make infinite ravens, replacing each dead raven with a new one, though you could only ever had 1 at a time)

Re: modifying time it takes for summoned allies to appear
 

I think it is in Supers that there is delayed time. It's a limitation that could be applied to Allies.

Re: modifying time it takes for summoned allies to appear
 

I haven't been able to find it yet, though in the process of searching Supers I noticed what looks like a few mistakes on pg 85. The Barnstormer mentions "as an IQ 0 character, it’s a Minion (+50%)"

This adjusts a point value of 1 (x3 for frequency) to 4.5, but B38 says "+0% if the Minion has IQ 0 or Slave Mentality" so since it fulfills once of the two possible conditions, the enhancement should have no cost...

Re: modifying time it takes for summoned allies to appear
 

Sorry wrong book.

There is Onset B113 and also Takes Extra Time B115.

I think the latter is more applicable and it comes in levels. However, it must be based on the realistic time allowance. Allies could be waiting in a Van or at a base etc.

Re: modifying time it takes for summoned allies to appear
 

I don't have Supers, so maybe. However what B38 actually says is "+0% if the Minion has IQ 0 or Slave Mentality..., as the benefits... are offset by the need for close supervision; +50% otherwise." If The Barnstormer doesn't, (or his Minions don't) require close supervision, it's +50% and not +0%, even if they are IQ 0 or have Slave Mentality (unless the benefits are offset by a different limitation equivalent to -50%).

Re: modifying time it takes for summoned allies to appear
 

I would suspect that the appearance of a Summonable Ally as described on B38 is instant (at the end of your Concentrate). I would think that the key to Powers p. 41 is that the Summonable Ally appears nearby, which covers a multitude of sins, and the time it takes to get from "nearby" to the summoner from "nearby" is what is at issue. If your Summonable Ally is a Cavalry Horse (B459) and it appears 16 yards away, it'll be beside you in 1 turn because its ground speed is 16. Summon that same horse in deep water at the same distance and it's be 16 seconds getting beside you at swimming speed 1, or more likely, 10 seconds at swimming speed 1.6. Hence the variability in time.

Bringing forth new allies is only an option when the power is first selected. You can't switch between new allies and the same allies thereafter. (Barring the introduction of a new type of ally. If the GM is willing to keep up with the paperwork and you have modular abilities, you might get the same goblin warrior every time, but a new fire elemental every time.)

Powers p. 95 about creating material illusions recommends using Summonable Ally which is created from thin air but "nearby" would probably be Illusion's 2 yard radius. Having the real material at hand probably doesn't speed the summoning up any more than the absence would slow it down or make it impossible.

Powers p. 29 and Powers p. 41 don't contradict each other. P. 29 says that the GM may allow Talent to affect reaction rolls for Summonable Allies and p. 41 assumes that that is what the GM did do.

Re: modifying time it takes for summoned allies to appear
 

Allies is one of my favorite advantages, perhaps the first one I modified and the one I have been playing with the most.

For you, I have these ideas:

1. Buying cosmic "I can summon my ally instantly anywhere"; you can build this with the Basic Book.
   
2. Luck "wishing" with a limitation for "only when summoning allies" (I like this one, its the simplest way). You can build this using GURPS - Powers.
   
3. The other would be making a charm or using magic items to trigger an instant summoning. Check the charms from GURPS Thaumatology - Ritual Path Magic. Also, The book GURPS - Magic items 1, features the "Demon Wand" on p. 103 (I think this is a 3e book).

Finally, further advice: Remember you can conjure an ally, if you buy it with the enhancement "minion", then your ally can die but you can conjure another after 24 hours. That's on GURPS Dungeon Fantasy - Summoners. If you put another cosmic modifier on that, you may remove the 24 hour wait.

Re: modifying time it takes for summoned allies to appear
 

Perhaps using the basic advantage guidelines, using Summonable Ally should cause them to appear 10 seconds after using Concentrate at a location of your choice within 100 yards?

Re: modifying time it takes for summoned allies to appear
 

Under the basic advantage guidelines, I buy no roll required and that is all. This means The NPC is always present; if you dismiss it, IMO it goes somewhere else w/o actually leaving you. For example, it goes a parallel dimension or becomes part of your own energy, your soul, etc.

On the other hand, basic also says you can amicably part ways with your allies, and says you may buy another one using its points.

So, imagine you dismiss your ally a create another out of thin air, from a silver-print of yours (e.g. your mana + memories) which keeps your (minion) ally up-to-date. You just concentrate and it instantly appears before you. No GM intervention (as I see it).

If you feel constrained by the note on the book of powers, buy an unusual background or cosmic, to bypass it.

What do you think?

Re: modifying time it takes for summoned allies to appear
 

Yes, it's safe to assume that an "always present" summonable ally can be summoned in a second, although it probably won't stay long if you are summoning a water elemental in a volcano.