Regarding unit massing/dogpiling, I'm not at all against it but I also think in some context we have to consider a potential larger picture scheme..
If we were to move foward FP to an Ongoing Sandbox game with hypothetically say 25 planets even, are our units spread out across the Galaxy more and thus not able to particpate in the same battle en masse?, so is a battle with..
4VSDs & 4 RAFs & 24 SF/AUX vs 4 PBCs, 2 MCRVs and 40 SF/AUX something we are going to see in that arena? or is this more like the Battle of Jakku scenario in the FP Universe? Personally, I think there's more strategical benefit to placing your ships apart anyways. At the very least, you need to cover 2 different headings even from the same grid space to make sure your field of fire is a little wider.. at least that's my modus.. i'd rather be shooting at you with multiple units from multiple directions vs multiple from one even if it's only for the sake of meaningless narrative in my head ;p
Also, you run in to the problem of grid size. If its' 2 Heavy per grid space, well you're already spilling over in to the G Column because you cannot deploy 8 Heavys (4VSDs, 4RAFs) in the 3 H grid spaces.
Consider perhaps phasing it in but in a lighter fashion at first. Phase 1 if this grid space occupancy limitations route would be like..
1 Grid Space per Players Capships.
That is, Opposing Capships CANNOT end their turns in the same grid space. If an Enemy ship moves in to and ends it's turn in your grid space, it is considered to have Rammed you, taking 50% of it's current hull strength in damage itself and dealing 33.3% of it's hull strength to one opposing ship in that location.
So then in the game it plays out also more organic kind of as a deliberate move thats bad for everyone as opposed to just an overhead limitation.
Not you would have to END your move in the same grid space as opponents capships, moving through in the course of a full move has no effect.