Online Multiplayer Object - preferably something that automatically controls object positions so you dont have to manually assign packets for every single freaking thing like in the MOO objects for TGF/MMF.
Minimap Object - for making minimaps easily... would be nice if they had a "scale" feature as well so you could toggle the area around the tracked object easily.
Inventory Control Object - Inventory control has always been a struggle in making any kind of RPG game, or any game really if you can carry more than 2 things at a time... Some kind of inventory with visual array would be really nice. This is the one thing that always annoyed me the most when making RPGs, and is usually why I never committed myself to sticking with an RPG style game... Making inventory screens that work well always sucks.
Dynamic Path Movement - OK so path movement sucks becuase it just follows a single path... but how about dynamic path movement? Draw your path(s), with intersections and all... and the object follwing the path will randomly choose which part of the path to take! This would be awesome for example say, enemies that could go along several corridors in a top down shooter game, but you want an element of random choices instead of knowing exactly where the enemy will go each time... or cars being able to pick which road they want to drive on. Turn here or go straight?
Just some ideas I have at the moment... will add more as I think of them.
~Sol