Hi jumpman.
Fur shader is waste of time and waste of gpu power. You can forget about it. Since i'm still using A7, i can't say aything about sprite instancing.
I am using model. I don't need vertex animation and while operation. I can animate foliages&grasses with shader. it's simple. About the "pushing it out of the way when an object touches the model.": I never try that but i think you can do it with event and shader like this: (not grasses but weeds and bushes)
//Lite-c
if(event_type==EVENT_FRICTION)
my.skill41=floatv(1)
...
//shader
if(vecSkill41.x==1)
do animation
But i don't think it's necessary. Players may not pay attention to them, especially in the action games.
in a nutshell I prefer the model.
Here is what and how i'm doing.
Edit:I did not see the post of superku when I wrote this. I also agree with him.
Edit2:if there is a misunderstanding, i was talking about specific object when i point to vecskill41.