Spellpoints Redux (3.5)

[Theodoxus]

I love the idea of spellpoints... probably my decades of playing CRPGs, but they just make sense to me.

I'm thinking for my next campaign to alter the UA version by changing the following:

1) Spellpoints regenerate naturally on their own, fully, every 8 hours (probably going use 15 minutes as the smallest gradient).
2) ASF no longer exists. While most classes still won't get access to armor (arcane casters, specifically) wearing armor won't hinder their ability to cast spells, rather it will reduce their number of spellpoints available by the total % the ASF would have incurred. This penalty can be negated by feats, class features and special materials/enhancements.

My question to y'all is, would these changes generate any issues if you were playing under them?

My only unknown right now is whether the ASF change penalty should apply retroactively or not. IE, a Wizard with 100 sp, dons armor with a total ASF of 50%. He now has 50 sp. He casts a 5 point spell, so he has 45. When he takes the armor off, should he still have 45 (the armor literally removes 50% of his spell points), should he have 95 (the armor suppresses 50% of his spell points) or should he have 90 (the armor suppresses 50%, but any spent while suppressed are gone, effectively doubling his suppressed points when the armor is removed)

The last one would be a logistics nightmare for percentages over 50% - he'd get more SPs back than he'd normally have... so I guess that one's right out.

thoughts?

[Siosilvar]

100 with 65% ASF = 35 points left. Spend 5, 30/35 points left. Take off the armor, divide by 35% (100% - ASF). 85/100 spell points left.

[lesser_minion]

You'd have to apply the penalty to the cost of spells, I suspect.

Although to be honest, I really don't see the point of additional penalties for armoured casting. If they want to spend feats or caster level on it, good for them.

There's nothing even remotely sensible as reasons for them to be impeded go.