Mulled things over a bit, I have some additional suggestions. If they've already been mentioned then hey, here's one more person who would appreciate their implementations!
Access/mutate entity positions, scales and rotations. My rough and painstaking implementation of a HUD required animating plain images in GIMP and exporting them as a series of frames which I posted as billboards attached to the player lantern. It was great but it was a pain to tweak things in the animation. It would be really nice to be able to simply transform entities directly!
Custom shaders? Please?
Would be nice to be able to tweak the glow effects on monsters and items or implement new screen effects this way. I know it isn't an easy thing to implement, but I'm still hopeful.
Better animation control for entities. There's a function already for animating entities, but it'd be nice to split it up into smaller functions e.g.
PlayPropAnimation(string who, string anim, bool loop); SetPropAnimationSpeed(string who, float s); I'm also not sure if these work properly on enemies. Would be very useful to use them for enemies doing special actions like opening a door without breaking it, or picking up an item.
Assign Kaernk (did I spell that right)? path nodes. As far as I can remember the river fishies will gladly follow path nodes but will not respond to path node assignment like grunt or brute enemies will with
AddEnemyPatrolNode. A workaround would be to spawn food items near nodes you want them to travel too, but it would be nice to have a simple function to do this for us.
In general it would be nice for a lot of the existing script functions to provide more of a control interface rather than a task-oriented interface. A lot are "fire and forget", but it would be nice to have more explicit control of things: allow us to get/set absolute positions/dimensions/velocities/speed of arbitrary entities, objects or their properties.