if i prefer vana run solo

Is this set specifically for Firestorm Citadel? You should have said so at the start. It depends on how good you are. If you're very good, then you can do all of FSC quickly with a Blitz Needle and any armor.

In general, there must be a hundred threads on how to choose guns, but here is the summary: You want at least two damage types. Probably they should be non-normal, but there are some normal guns, such as Iron Slug, that are good. As far as styles go:
* alchemers: hard to use, high damage, interesting
* antiguas: easy to use, medium damage, boring
* autoguns: hard, high damage, boring
* blasters: easy, medium damage, boring
* catalyzers: supposedly ruined by the gunner update
* magnuses: hard, high damage, interesting
* mixmasters: [I've never used one. They're hard to get.]
* pulsars: hard, medium damage, interesting; mainly for crowd control rather than damage
* tortoguns: hard, medium damage?, interesting

For armor, I can't tell you any more than my guide already tells you. It all depends on how good you are.

If you want a simple recommendation, I'd say (A) Blitz Needle and (B) Storm Driver or Iron Slug. Not Hail Driver, because it often breaks its freeze. And I'd say (A) Chaos Cloak and (B) Perfect Mask of Seerus or Sacred Firefly Shade Armor. For shields consider Swiftstrike Buckler or Grey Owlite Shield.

I'll add in the tortoguns. Thanks.

The pulsars have a bad reputation, because so many players abuse them. But in the hands of a skilled, considerate player, they can do things that other weapons can't. You can use them to shape a crowd, for example plowing a tunnel through your enemies. And you can do it from afar. Using them well takes skill. That's why they're interesting to me.

Yes, Chaos is recommended by my armor guide (along with Black Kat). But this poster seems to want something more defensive. Because he (or she) is using only guns, he can get offense that is nearly as good as Chaos, with much better defense than Chaos.

Yes, alchemers have great regular attacks, in addition to their great charge attacks. They have a steep learning curve, but I like that about them.

Nope charging is always a waste unless you need more mileage for your bullet to hit a further out of range target that can't be reached with a regular shot. It's not a waste for people who likes to waste time and finds pleasure charging every bullet to watch a fired oversized bullet.

I am talking about true efficiency. You'll not clear a group of monsters faster than gun switching. Like any charging ability, it steps down your mobility 2 seconds or more when it's fired. And every charged shot fired is far less DPS than switching. If you're not getting similar results, you're doing something wrong.