A feature i would like to see is very simple. I would like to not have to type "2*x" for every time i want to multiply.
Generally, all of us think "2x" and having to type "2*x" takes extra long since the "*" symbol detracts somewhat from the typing. Also, it slows down copying expressions out of a text, since we have to manually add the multiplication sign.
I know it seems like a picky thing to request, but it would save me from a lot of syntax errors that i have to go back and edit.