made this chart a while ago. my apologies if the formatting is awfull. divide the utility in the chart by 1+(current skill power) to get the incremental utility. (or [1-current skill power] in the case of fusion)
freeze*/bolt/beam/etc: 0.5% per level, tops. amplifiers: 0.6% per level. (average). orange: 1%/ 6% per level. (1% if below level 100: 4% if above level 100. ) yellow, red, black: 5% per level, each. green/blue/purple/cyan: usually worthless. resonance (if you have it): 3%/1.5% per level. ** True colors: 6%/10%/13% (6 if using pure gems for damage, 10 if using red/yellow, 13% if using red/yellow/black) fusion: roughly 1.2% per level: is worth ~1.6% per level at level 15. (I have not reached the final cap for fusion yet.) mana stream: 4%/8%/0.5% (not angering/doing lots of optimized angering/mana farming)
traps: 0.2%/5%/15% (below 100, using pure orange traps to supplement/using red/orange/black traps) *freeze becomes truly usefull when it is maxed for perma-freeze.
I haven't tested whether damage boosts are affected that way or not, but since the black special no longer amps, it's not worth sticking black into an amp gem, even if the damage is boosted.
lets look at trap masteries and true colors. lets say we're in the mana farming stage.
So each level of true colors is worth 13% more mana(but you have to get it in batches of 3), and each level of traps is worth [s]15[/s] 20% more mana.
Lets ignore the "divide by 1+current power" for now.
lets say we have level 6 true colors and level 15 trap mastery. each true colors level is worth 13% mana gain, and each trap mastery level is worth 20. but at 7 per level, true colors yields 2% mana gain per skillpoint, while trap mastery only yields 1% more mana gain per skillpoint: so, to balance your skills, either take points out of trap masteries or add points into true colors.
now lets bring the "divide by 1+power"back into play.
at level 20, trap masteries gives "+100% to...". its NET worth is much more than that, but you want the "+100%" when compute the incremental power of the next level. 1+100%=1+1=2.
so. normally, it's worth 20% per level, so now it'll be worth 20%/2=10% per level....and a measly .476% per skillpoint.
at level 15, true colorsmasteries is worth 13%/1.5=8.666%. or .52525% per level.
So, if you keep trap mastery at 20, you should get the next three levels in true colors...if you can afford the skill points. (since true colors should only be leveled in batches of three, leftovers should go to trap mastery)
No, damage is not boosted, as amp buffs = the base stats of gem, unmodified by blood or pool.
Also, just saying, the amount of specials/damage shown given by an amp to a black or white - colored gem, is the amount before trap modifiers or blood/pool modifiers go into effect.
