Other than invalidating the feat, ading a charge rule into the game doesn't break anything that I've seen. I played in 2 games that had charge rules, and both worked fine. In both the rule was very similar:
The rule: If you use your action to take the dash action and all of your movement has been in a straight line, then you may make one melee attack or one thrown weapon attack so long as the target is in line with the movement you've taken. Your speed drops to 0 until the end of turn and cannot be increased for any reason once you make the attack.
The difference was in peripheral rules around charging, including rules about setting weapons against a charge.
Technically, I also played in a game that had a homebrew warlord class that had a mechanic that allowed charging. That class, amongst other things, gave benefits to their allies so long as the allies could hear the warlord's commands, and one of those benefits was that they could make charge attacks. It was a fun class, I think, but the player running the PC was a ... challenging person.
