Change the goblin from 5 XP per 85 conversion points to 5 stacking XP per 100 conversion points (5 XP from first conversion, 10 XP from second, 15 XP from third...)
All characters gain the benefit of a full heal and mana restore for every 50 XP after level 10.
This allows Goblins to accrue an amount of XP that is actually appreciable at higher levels, and on levels where hitting level 10 is a forgone conclusion (or if Tikki Tooki or IMAWAL are used) they can still benefit from having additional XP.