None of these suggestions are very important.
First of all, I would love to see some new burnt out tank models. The ones we have now are very nice, but I always see the same burnt out tanks with broken tracks and busted cannons. New models would be cool to look at.
Next, new animations overall would be nice to see. Reload animations, burning animations, death animations. Especially downed animations. There have been times when I am on my tummy in cover and I get downed, my soldier brings himself to his knees, poking his head out of cover and I am shot. Maybe a new lying down downed position would help, it would also look nice.
It would also be nice to lie down on your back.
More reload animations for weapons would be cool.
New animations for commanders peeking out of tanks.
New animations for crew entering tanks, I would like to see each crew member enter their respective hatch. It has been done in other games.