I am not a fan of spending an action to position myself, since the main point of combat in this game is to outposition masses of enemies and deny their actions.
It is hardly a matter of “our positioning” if everyone can more freely, all the time without any hindering. You can still disengage and push I think, which should still be greatly powerful (potentially too powerful, but I am speculating). At least engagement will have some value now.
As to moving around - there are still class abilitites/spells that will allow to disengage as bonus action (trigger engagement more safely). I can’t imagine the game being worse off with this change.
