So if I didn't like Wing because the main character was way too edgy, is there another Gundam worth trying or are most of them like that?
Well, angst and edge are two different things. Angst usually implies a certain degree of whining, and quite a bit of emotional turmoil. Edginess is more about stoic bad-ass characters who get their hands dirty. Edgy characters usually downplay emotional involvement as much as possible.
And it is true that Wing's primary protagonist was quite "edgy." But you shouldn't have too much to worry about, as the average Gundam protagonist usually leans much more heavily toward angst as opposed to edge. Given your tastes, you might want to avoid the Gundam 00 series. That series protagonist has a lot in common with Wing's, and definitely trends toward edginess. Seed is probably fine for you, very little edginess in that one, almost entirely angst. And the original Universal Century run should probably be no problem for you either. The edgiest characters in those tend to be the antagonists, not the protagonists. And they usually don't lean on those characters too heavily. G-Gundam might be your thing, as that is a colorful combination of angst and cheesiness, but only pays lip service to edginess.
I haven't seen Iron-Blooded Orphans yet, but from what I've heard you might want to give it a pass, as it's level of edge is likely quite high. I would recommend the Build Fighters series though. That one is actually quite light-hearted, and much more focused on positivity and enthusiasm.