Where on earth did you get these numbers... I'm not sure how accurate they are. :SI have run some stats on the twink issue at level 19 where the problem is worst.
10-50% = The variance in spell/ability damage/healing due to spell/ability ranks available at different levels.
0-20% = The variance in damage/healing due to non-twink gear variance available at different levels.
10-70% = The variance in damage/healing due to normal RIFT rules without twinks.
10-40% = The variance in damage/healing from a well-geared 19 vs. a twink.
Warrior 10%, Rogue 20%, Cleric 30%, Mage 40%.
20-110%= The total disparity between a well-geared level 10 vs. a 19 twink.
36% = The proportion of warfront disparity at 10-19 due to twinking.
As you can see, almost half the problem is due to spell/ability ranks. Can they not scale as you level?
This problem decreases with higher levels - and so does the twink advantage.
The main twink issue is that they have their main advantage at 19 - and since they have no way to fight among themselves, the warfront levellers and noobs get dragged into the fight.