I'm talking about the following terms:
Swordy
Gunner
Bomber
Hybrid
I hardly ever see anyone good using all swords seriously.. if anything, they bring swords and guns to the fight. When I plan my armor, I don't just go "Welp, I'm a hybrid, best bring chaos + bombs and guns and swords. Derp." I bring swordy/gunner/specialist armor too, and I have a plan to kill everything I meet.
Here are two of the sets I choose from:
"Assassin"
+Dread Venom Striker
+Valiance/another gun
+Maskeraith@Any Shadow Cloak/Drakon@Backfire Barrier
+Sword buffs, MSI appreciated
Strategy: Use valiance to stay alive while dealing small amounts of damage. Then, when there are enemies far off or menders present, or anything that should be dealt with ASAP, I use deadly shadow cloak or backfire barrier to sneak up on them or otherwise overwhelm them by running up. This almost always guarantees that whatever I'm fighting dies, and helps my team marginally more than just spamming brandishes would.
"Crowd Control Support"
+Sudaruska/Brandishes/Divine Avenger
+A vortex bomb/Shivermist/Voltaic Tempest
+One part chaos
+One part defense armor
+Drakon/Seraphynx
+Bomb or sword CTR perk
Strategy: Use your sword for small encounters. Whenever there are 5+ enemies, plant a bomb or two and attempt to smash them. If you noticed your team taking advantage of your bomb, let them and keep spamming it or switch to your sword and just fight normally.
But that isn't the point
There's nothing wrong with focusing on swords or guns as your "class", but it's kind of unrealistic and no matter which you choose, you'll have to find a strategy to use within that set of items, and branching out will let you build far more and far more interesting sets.
What if instead of saying "swordy" or "gunner", we asked what role people wanted to play, and broke it up into that instead? We could list 'classes' or roles based on what they actually did for the party, like so:
+Assassin = Kills priority targets; defaults to safe play otherwise
+Defensive Support = Focuses on keeping the team safe + helping the team
+Offensive Support = Focuses on softening mobs + helping the team
+Soldier = Focuses on DPS and killing everything in sight
+Drunken Master = Focuses on control over the environment and otherwise manipulating the situation.
The general idea is good. Here is an example, or at least a related story.
As "everybody knows", sworders rush into combat and get beaten up, while gunners spread status and cooly pick off monsters from afar. But in Heart of Ice, my teammates frequently unleash Blitz Needle charges on everything. While they are charging and recovering, they are vulnerable to greavers, devilites, etc. In stand in front of them, interrupting monsters with Final Flourish first strokes, and sometimes shielding. I'm playing pure defense, waiting for the Blitzers to unleash the offense. This role reversal is made possible by the extreme all-or-nothing dynamics of Autogun charges. Are there other interesting dynamics like this in the game? I guess vortex bombs.
Perhaps what I'm saying is that character classes, as you envision them, make sense only in the context of a team. It's not even really about the individual player's "style". It's about what group he's in today, what group tomorrow, etc.
There seems to be some overlap between the categories. Presumably the Soldier does his DPS against "priority targets". "Keeping the team safe" is almost always "controlling the environment".