Magic Weapons: Innate Attack vs Signature Gear

[talam]

I'm porting a Cortex-based steam-tech fantasy game of mine to Gurps 4e. Because of how character creation is so much more extensive, I've been making random characters to try and familiarize myself with the system, in the hopes that I can adequately help my players if they have problems.

My current 'what the hell' is magic weapons. I've searched the faq and tried sifting deep into the forums (I got till page 8) but haven't really found any solid solution yet. My issue is thus:

On the faq: it says that a good way to represent magic weapons is using innate attack. For melee-weapons, the Melee attack modifier with the ST-Based enhancement was the way to go. Fine, dandy.

However, within the Magic section of the Basic set and Gurps: Magic, it details how much magic weapons would cost. Something like energy cost * 25 = $ for enchantment alone. Also good.

My confusion comes from the point disparity between the two, and little quirky issues. For one character, I'm building twin short swords, with an armor divisor mod of 3, the ability to affect insubstantial and +1 to damage.

To build this with innate attack - Melee attack (c, 1) -20%, ST-Based +100%, Dual +10%, Affect Insubstantial +20%, Armor Divisor (3) + 100%, Switchable +10%. Since the weapon gives a +1 to damage, I'd use .3 of a die, it's cutting damage, so it's .3 * 7 modified by a +220% modifier which comes out to 7 points.

To build this with signature gear - Penetrating weapon at Armor Divisor 3 is 750 energy points, Puissance at +1 is 250 and Ghost weapon is 250 per pound. A single short sword is 2 pounds, so Ghost weapon is 500. Add it up, that's 1500 energy points needed to load a short sword with those enchantments. Since it's $25 per energy point, that's $37500. Since I'm setting it roughly at TL 5-ish, average starting wealth is $5000, so every point of signature gear gives me $2500. Which means to buy just one short sword, it costs 15 points in signature gear. If I want both, that's 30.

So at this point, I'm trying to see what kind of benefit there is getting the short swords via signature gear instead of innate attack and/or the best method overall. A quirk I'm having with innate attack period is how exactly do you hit with a melee innate attack: it says that the innate attack skill is only for ranged and that brawling is for the other stuff, but I'm trying to represent magic short swords. I also want to be able to use fast-draw as well. As a GM, I can just say 'use short sword instead and fast-draw is a go' but I'm trying to figure out if there's a by-the-book way I can solve this.