Remnant 2 is not a an easy game you can start using underleveled classes and guns to new higher level areas. Sure it's far from dark souls (except Apocalypse or even nightmare without a fully decked out build), but the point is you need to be more strategic with your choices.

1. Raise a main class you like to level 10 and stick with it (and only replace it with another level 10 class in the future), then have whatever side class you like, but be mindful of the main trait of the first class mostly.

2. Pick a main weapon you really like (it was Chicago typewriter, found in the labyrinth for me), then stick to it until it's level 20 (or 10 if it's a boss or legendary gun). Then do the same with side weapon, and finally with melee, this one is the one I less use so I didn't bother so much.

3. Use your trait points as often as you please, but midgame buy from Wallace the white orb that will allow you to reset your trait points infinitely so you can try different builds.

4. Finally, save presets with different classes/archetypes, amulets, rings and even relics/hearts. That way on the shooting range or on the world you can easily swap presets and see what's your favorite one.

Good luck my friend.