But every weapon is already inherently different. I'll use the Incisor as an example again. Its a cool gun, but its damage is far too much of a nerf when compared to the other guns. It may fire in 3 round bursts, but the damage still doesnt compare. If it were all about diversity, then why does the BW do less damage per shot than the Widow? It was for the sake of balance.
Some level of balance no doubt. But that's the charm of having different weapons that do different things at different levels of effectiveness. I'll use the Incisor for fun too... and I actually do quite well with the Incisor. Vs. the one shot Widow, which I just absolutely can't stand, no matter how much damage it does. Incisor does get you through shield gate, which is infnitely more valuable.
Should the Incisor get a buff? Should the Widow be nerfed? Nope, I do agree there is balance, and the balance in the game is just fine. There are people that argue the Widow is infinitely superior to the BW, so should the BW get buffed because its an Ultra Rare? Nope, once again, its all about preference. Just about every sniper in the game is relevant. The Krysae just does things differently, its your sniper for dummies rifle. Look at its base damage stats, does it measure up to even the BW? Nope.
But the Falcon invalidated the entire AR weapon class. Why use any of the other Rare ARs when you had a Falcon? It was ridiculous, but it was nerfed too harshly. That is BioWares fault, I didnt ask for that.
It only does that once again, if people are so hung up about their scores or using the best class/power/loadout all the time. People complain about the GPR like its totally irrelevant yet I've made plenty good use out of it. Phaeston too. Revenant too. If anything, all the Falcon nerf did was make the Falcon irrelevant, in the AR class, to an average player.
Irrelevance of weapons (except SMGs) only happens because some people get so caught up with being the best, using the best, scoring the highest. What you need is a change of player attitudes, but you're not going to see those sorts change their skins anytime soon.
When you pick the difficulty level is when the difficulty is decided. Your loadout shouldnt make the game easier directly, it gives you a set of tools that plays to your personal strengths and that of your character. At its most basic, the character is just a tool too that you use to play against the system at play.
Loadouts should matter. If anyone can pick any weapon and do well with anything, then there is no point in the unlock system, or choosing loadouts. Might as well give everyone the same Model X, and be done with it. And the higher the difficulty level, the more your loadout counts, that's also correct.
Note - I'm also ok with the Eagle being bad. Rarity is just that, not necessarily how good a weapon is, but rather, how rare it is, ie. how hard it might be to obtain. No idea if its really as bad as people say, I have a Crusader though, use it sometimes, its got its drawbacks and isn't the Valiant, but its gets it relevance being a sniper shotgun.
People that let carrying the perfect loadout and builds dictate how they play will constantly find themselves less challenged and probably end up having a lot less fun.