The weird thing is that a Half-Elf also is a Half-Human. But how much of that do return in the character abilities:
- Preferred Class: Highest
- Ability Modifiers: None
The 1st probably doesn't even get noted in most cases. It has no use at all for singleclass characters and multiclass characters where both classes level at the same speed.
The 2nd gets noted even less. Humans are pretty dull with no ability modifiers.
As for bonuses, it's obvious that the Elf has far better bonusses than the Half-Elf. The 2 influences from it's Human parent aren't bonuses, just traits (The preferred class is not always a bonus. For example, an Elf Fgt3/Rog3/Wiz1 endures no XP penalties, while a Half-Elf Fgt3/Rog3/Wiz1 does).
How minor these 2 Human influences are to the Half-Elf, the Half-Orc has even less. No Human traits at all. The Orc however is not a playable race, so the comparison with Orc abilities are made far less, but they're still lacking. In a campaign where Orcs are permitted, the Half-Orcs would suffer as much as the Half-Elves.
What would be nice is a heritage system. Each common race should have racial features and heritage features. The heritage features would be about half the racial features. Then when 2 races mix up, the child receives the heritage features of both parents. For example:
Human heritage abilities:
- No ability modifiers
- +1 skillpoint per level (4 at level 1)
- Preferred Class: Highest
Elven heritage abilities:
- +1 Dex, -1 Con
- +1 save against enchantments
- Lowlight Vision
- +1 Listen, Search, Spot
Then when you want to play a Half-Elf, you just ask permission from your DM and if he allows it, you take the heritage abilities from Human and Elf and apply both. If neither of the parents are Human, the DM picks the Preferred Class of one of the parents as the Preferred Class for the child.
You would just have to make one heritage ability set per race, and you get the abilities for numerous crossbreeds, which stops the problem of almost all crossbreeds having a human parent. Of course the DM still has saying over which crossbreeds do or don't exist, but if they do exist, the stats are there.