I'm not often a bells and whistles type, I can overlook quite a bit so long as the core game play is in a good place.
I think the thing I'd like to see now are some more realistic and variety wicket celebrations. The number of times I've seen various bowlers do their aeroplane celebration before getting mobbed by their team mates. Let's have some bowlers running off up the pitch with an arm in the air, or standing still and fist pumping, or jumping in the air, or, well, anything really!
As I say, hugely cosmetic, but something that's struck me more in recent weeks.