No, because you’re giving +1 damage per 2 levels. Heroic dragonshard + iron armbands of power + weapon/implement focus is +4 (5 if you’re using silvery glow instead). Paragon dragonshard + IAoP + elemental damage feat (Fiery Blood, etc) is +10. Epic shard + IAoP + elemental damage feat is +15. So you’re basically providing them with those optimized choices for free. Suddenly a controller who hits 2 enemies at level 30 is doing 15+ 6 enhancement + say 8 or 9 ability score + 2d6 or something for the power is doing 1/4 of a standard monster’s hp per turn, or a defender is likely doing 40 on a hit and then damage if their mark is violated, etc. Basically, it means a good chance of finishing combats in 4 rounds or so, which keeps combats from being dragged out.
And it reduces the advantage of always focusing on one type of elemental damage, so there’s less pressure to always take a damage conversion weapon for optimization.