Drops and exp for supporter classes

I had quite some talks about how supporter classes (runner, healer, buffer, tanks etc.) can get a more fair share of exp and loot and here is my idea for a fair system:

• The support skills only work for party members
• XP sharing in parties is mandatory (exp is distributed based on player level, lower lvl = less exp)
• Drops do not belong to who did the kill or the most damage, drops are distributed randomly between party members (low lvl chars have a lower chance of getting an item). A need/greed/resign system would be nice but most likely hard to implement
• pets would be very useful to pick up loot while the player is busy fighting/supporting