More animals both in the Nether and Overworld, more blocks, different block placement, the ability to turn off the current combat update, more craftable items, maybe and definitely more stuff in the ocean and sky, flying animals.
The only thing I'm interested from 1.9 is the Elytra. I'll check it out when the update comes out but most probably stick with 1.8 because I just like it more.
I'm currently trying to make my first skin and I'm using MCSkin3D. Don't really know how to use it so it's pretty difficult but I'm getting there I also have a ton of tutorial and reference tabs open so if I memorize it all, I should be good *dizzy*
Anyway, I don't intend to copy or steal skins (of course not Dx) and as much as I want to look up other people's ways of shading, I won't. I'm just trying to learn how to base the skin and stuff and later I'll get on to earning how to shade. It'll feel much better once I actually master some way of shading that I thought up myself than stole from someone.