Gravity, however, is a completely different matter.
I understand that some people may not like throwing opponents from heights, but this will not change because they would have to rebuild practically the entire game. Making it an action instead of a bonus action will not change the effectiveness of this tactic.
But limiting the distance to 5ft., making enemies smarter to avoid ledges, and not guaranteeing a 100% success from invisibility would. The buffed up Shove distance is probably the biggest offender. If you would need 2 or 3 Shoves to push someone over the edge they would get a chance to react and move to safety, or you would need multiple characters teaming up to push the same target.
Making it an action would also mean it's not a free thing you can attempt in addition to attacking or casting spells every turn. Right now, even the 9 Strength Wizard will spam Shoves just because they're free. If it's a choice between a weak Shove and doing something else you're actually good at, you probably won't Shove much with that character. Big difference between always Shoving and rarely Shoving.
