Home brew or house rules for my 5e games
The 5e DMG describes an Initiative Variant in the Combat Options called “Side Initiative”. This is similar but also doesn’t take away the initiative mechanic. Some players take feats and other options that improve their Initiative so I don’t want to remove that part of the game.
Each creature in the combat rolls Initiative as per the normal rules. The highest roll for a “side” will represent the Initiative for that entire “side”.
All creatures on a side may take their movement and actions in any order. The players are responsible for coordinating tactical efforts and the players must inform the DM when all their action and movement are compete. Some party’s elect a team leader to assist in their sides coordination and communication with the DM.