Right now I am saving some weapons instead of selling them for gel. I was under the impression that I should save some weapons for new party members that come in. However, I was thinking that party members I lose would get me their weapons back. Should I sell the weapons for gels? Should I save them and sell them for credits later on? Should I keep extras around for new party members coming in? I'm still new to the game, trying to get the hang of things.

Gel is good if your on a higher difficulty since you may need to repair the MAKO, but other than that, if you're pretty decent at opening stuff. The little Simon says type minigame. You really shouldn't need that much gel. Also, you get new weapons pretty frequently provided you fight.

Basically, I try to get a bit of a stock of omnigel and then sell the rest.

At a certain point, you're going to come across so muck crap that you pick up you won't know what to do with them. Eventually you would have equipped everyone with a weapon and upgrades.

Halfway through my second playthrough, it got to the point where I didn't need more weapons or credits, so instead of selling them, I just automatically converted everything to omni-gel. You get go ahead and use omni-gel to unlock everything. Chances are you'll find some more items to convert and you'll be back up to the amount you had before.

I only convert things to gel when I am out on a mission and can't store any more weapons

Some various answers here, but looks like saving them and selling them for credits is the way to go early on, then converting to omni-gel late in the game. I did encounter a lock early in the game, didn't expect the mini-game, and failed it instantly. I had to convert most of my weapons to omni-gel just to unlock it. Next time I need to make sure I save my game right before I try to unlock something, just in case I fail. I don't want to be spending so much of that gel on unlocking things. I know it may seem cheap to reload a game like that though

just sell everything that's not better than what u have until level 40ish after that you should have 3 mill plus. if playing on insanity just make sure you save up and buy the specter class weapons asap!

Yeah, I wasn't sure how often I'd get new party members, so I was saving up extra weapons for them. I may sell some soon, though I haven't gotten far in the game.