From what I've seen with raid armor you are probably better off using other legendary + exotic armor for stats and perks you want. There's no point in using armor with perks that gives more super energy from killing enemies in the vault if you're not actually doing the raid. Besides factions can still be useful for when you know what stats you want between INT+STR, INT+DIS, or DIS+STR. You'll still be at 28 or 29 if you max out your armor anyway and can still do PvP(I'd say you're better off not using raid armor in pvp tbh), nightfall, level 28 weekly strikes, and the normal raid. So you're just missing out on 12 points of light (9 if you use an exotic) and a few perks that make the raid a tiny bit easier, while you can get perks like more ammo for weapons, faster reload for weapons, melee restoring grenade energy, grenade restoring melee energy, etc. Personally I would like to have another way to hit 30 (like Iron Banner armor), but outside of the raid you don't really gain anything by being 30 and it could straight up outclass raid armor if it had the right stats/perks.