My needs are pretty straight forward - I don't mind a little weight, but i focus my gear on hunting. I do a lot of prone and rested shooting/hunting.
I built another AR for myself last year with 3 uppers - a 22" 204, an 18" 6.8, and a 20" 223/5.56 - with the intent for these 3 to be all I really need, but keeping a few others for specific uses. If I could only have 2 and couldn't specifically have an SBR and a 24" long gun, I'd modify choices a bit. So, instead of at least 3 rifles with 5 total uppers, and getting rid of about a dozen others:
Like most - I want a handy 5.56, and a more potent long gun.
1) 5.56/223 18" heavy barrel with 0.750" gas block (heavy, but nose light), adjustable gas block, ubr stock, Geiselle nm 2 stage, 15" handguard, back up sights, acog with 3x and 7x multipliers on QD flip mounts
2) 6-6.8 22" heavy barrel, same agb, Luth-AR, 15" handguard, Bushnell elite 4.5-30x50mm mil-dot, same geis 2 stage. I could be convinced to turn this over for a Dtech 25 wssm upper in 24", but for that kind of range and power, I don't mind swapping to a bolt gun. OR I could say this would instead be a Nemo Omen in .300win mag, but I assume that a proprietary AR-10+ doesn't count in this game.
That gives me a nice and handy 223/5.56 and a heartier long gun to bang with.