Put simply, it would improve the game massively. I know it's unlikely EA will take any notice, but I might as well at least try posting something.
- The old penalty and free kick mechanics. This year's are simply awful. Not even enjoyable in the slightest.
- Bring back trade offers (but only for untradable players or even have a loan system of up to 48 hours so that friends can loan you their cards.
- More casual online modes and tournaments. Why the heck did you even take them out? Now people barely touch FIFA during the week unless it's to trade.
- Simplify the squad building menus, the menus on FIFA 19 were much better.
Sort out these few basic things and FIFA automatically becomes a bit more enjoyable.