Additionally do I need to increase both span or just area? Can I just increase the length of the tip/root chord?
Here's how I
think I understand it, radically simplified into something one can use easily(ish).
What you should focus on is the area of the fin that's beyond the boundary layer. The boundary layer is <xx> thick, so the portion of the fin that's within <xx> of the airframe isn't doing you any good. Your tiny fins have only a little bit of area beyond the <xx> think boundary.
With that, and
if my understanding is right, and given a value for <xx> which I am totally unable to provide, you can see for yourself what you'd want to do. If you keep the same root and tip chords and just extend the span, you get long, skinny fins that will probably flutter badly. If you keep the span and just increase the chords then you get nothing but really tall strakes. So increase both, in order to have a reasonably shaped fin with enough area where it counts.
People, both the big guys and the hobbyists, have been doing this so long that they've settled in on solutions that work well. When you think of a "normal" or "typical" looking rocket, it looks that way because over a century of experience has shown that it works, so lots of rockets are build that way, so we see lots of pictures of rockets that look that way, and that's what we're used to, what we call "normal". If it looks normal, it's likely to be OK. If it looks odd, it may well be problematic. By the "looks normal" test, you're fins are too darn small.
Also the nozzle appeared to erode kinda weird.
What looks weird? It's almost perfectly circular. I do see that little chip at about 12:30 in the picture, but to my totally unqualified eye that looks miniscule and trivial.
Would I be crazy to buy a G motor and launch it with current fins before the next club launch(my parents have a bit of land up in the hills.
"Crazy" depends on the field conditions and the G motor's initial thrust. If you'll get sufficient guide exit speed, and you're very confident of successful and undamaged recovery, then no, it wouldn't be crazy. But I strongly suspect it would be a waste of time (and a G motor).
And finally, this: at the outset of this thread and build, you acknowledged that you are well aware of the KISS principle and that this "wildly overcomplicated" build might not be a good idea for a cert rocket, and that you were willing to take the risk. So, OK, you took the risk with eyes open, and it didn't work out. Nothing wrong with that. Now go build a normal looking rocket and get that cert.
Be glad it was just the chute.
