[Devil_Dante]

Well my man, your work is outstanding. First thing first, thanks for your time.

Now, the idea is to give him some extra pool to use only during fights, and nope: asking for some punches on the back won't work XD
Lucky for me, none of my players has a "munckhin" approach, so it won't be a problem.
So, these additional points he would have on top of his starting daily pool, should be used only during the fight, and for love of simplicity, any unused point would be erased after the fight ends. That's help book-keeping those numbers.

As far i've understood, in the simple way, if he uses all extra points (capped with the level bought), he has to heal in order to refill the pool again, or, as you said, they regenerate at the standard ratio.

The second way is more like i thought about it: there is a maximum cap (the level he decides to buy), and the pool can go up and down dinamically during the fight(i.e.: he hits for x damage and during the next turn he has x more tally to cast a spell, then he is wounded for y damage and has y extra tally to use).

The second build is way more cool. The only downside is the cost: quite expansive. For a 6 points pool (like that i think he wishes to have), we're talking of 30 points of DR and 15 points of ER= 45 points. Yes, he could use more the 30 points per fight in this way.

Now, in my setting, i set the starting tally at 20, with 20 of regeneration. According to the thaumatology rules about "increasing threshold: 5 points to increase the pool by 20%", this means 5 points give 4 tally. For regeneration, according to standard rule: 5 points per 5 tally per day.

With 45 points he can buy 20 extra tally per day and 20 regeneration per day.

That is, now, my only concern, from a Point-wise prospective.

But that's quite an answer <3