Alright, I'm getting a yes and no simultaneously so maybe a specific situation would help. Sorry if this is a bit long...
Say I want three factions to have the Vasari LRF. Two are the same "race", one is not, eg worm1, worm2, and space1.
I update the player entity files for all three to have FrigatePhaseLongRange.entity (if I'm keeping that name) and update the count within the player.entity file for each faction (assuming its being added and not replacing anything) but not the manifest (because the file itself already is in there once).
I keep the associated strings, models, meshes, effects, damage types, and abilities the same (since most are tied to that same entity file).
Each of the factions improves shields differently but there is a different entity for each of those researches as needed and they aren't directly linked to the ship.
I still use a single common research unlock for the ship that will have the same cost for the same ship in the same location of the research tree for each faction (and is in the player and manifest entity files once each as needed).
My questions then become:
1. Would this work at all? (as a base level)
2. Would it work well/efficiently? (what are the advantages/disadvantages if any)
3. Is it a poor practice? (like coding complicated parts without comments; it works but its a mess thats harder for others to follow)
Thanks again for the posts, sorry this got a bit long, enjoy the karma 
