Since half elves are still considered elves for negative effects, it would be reasonable that they share slightly more heritage with their elven parentage/aptitudes in the form of certain enhancement choices.

I'm suggesting to add Aerenal, Valenar, Ranged, and possibly Drow Melee/Ranged lines to Half Elves. To balance, perhaps add various Dilletante feats as additional optional prerequisites, that way Half Elven fighters would not NEED to take Dilletante: Fighter to qualify for the weapon enhancement lines.