Other options, although maybe not the best option, is to just watch the war for space play out.
But ultimately you likely will need to remove the fast growers at some point and replace with some slower ones. Overtime though it inevitable that one coral will end up dominating and taking over. In the end though corals are always at war for space, even in the wild, and overtime they either stand their ground to hold their territory, overgrow their neighbors or get overgrown by them instead.
In our tanks we are the designated caretakers and as such, we can choose to try and referee the situation the best we can or you can watch it play out