expertise adjustment suggestion

with the 30% spell dmg reduction our vital drain skill was additionally affected. the spell costs 50 mana to cast and regens mana 50% of dmg dealt to the target it appears. due to the spell dmg adjustment now at least as a lvl 67 this skill barely regens any more than the cost of the spell when used on mobs of similar lvl or above. Ideally, it would be great if the mana regen could be kicked up a little more than 50% of dmg dealt. But another alternative now is for us to invest training points into the expertise reduced in/evoking. This expertise reduces the cost of the spells in that alignment which includes the vital drain spell. I have confirmed this myself just before posting this. It reduces the cost by 1 mana point per lvl of the expertise thus making vital drain cost 49 with 1 train, 45 with 5 trains and so on. The stat requirement to upgrade this expertise requires both strength and wisdom. If this requirement could be changed to only wisdom or intelligence or even dexterity it would be really helpful and make an expertise useful as well. the requirement of strength and wisdom greatly limits train ability beyond lvl 3. I believe this expertise adjustment would help balance the mana regen ability without impacting anything else and since the increase from the expertise is only a 1 point reduction per train even if trained to 10 wouldn't cause too much of a boost to be considered OP and not unbalance anything else in the process.