Non-target average student declined BB trading ops offer, now having some second thoughts

Posting this under a throwaway. I'm feeling conflicted in a current career situation and would greatly appreciate any advice.

Backstory:
I graduated 2 years ago from a non-target school with a just-average GPA (~3.0). I joined a growing fintech company right out of school (interned there while in school). While I'm content with my job, I have casually started exploring other opportunities. As we've all said, fintech isn't a career. I've learned a lot so far (current role is in capital markets) but am starting to think about a next step.

A month ago, I received a LinkedIn message from a recruiter with a BB. They were looking to fill a trading ops role in their local offices. I responded with interest, went through three rounds of phone interviews, and was ultimately reconnected with HR to discuss an official offer.

At that point, I learned that they were looking at bringing me on one level lower than the title I had been interviewing for (given my experience, which I understand). With that, comp came in lower than expected. This was one of my big motivators for making a move right now. Their base comp offer was higher than my current base by approximately 20%. However, my current total comp is heavily weighted towards commissions/bonuses/other performance-based comp. In this new position, there are no bonuses or performance-based comp, but the interviewers from the group all stressed the opportunities for overtime at 1.5x normal pay. They said that this typically accounts for a substantial portion of total comp. I expect that this would put the total comp in-line with my current on-target-earnings. That said, the current environment has made commissions and bonuses more uncertain. I can't say if I'll even be near my on-target-earnings this year.

After much consideration, between the comp disparity and the uncertainty of making a move in this environment, I declined the offer. The HR representative was very understanding, asked to keep in touch with me, and we left the door open to discussing this bank as the next step in my career.

That was 2 weeks ago. Since then, I've been having second thoughts here and there and wondering what-if. The value of a BB offer for a non-target average student has set in a little more.

Questions:
1. What would you do in this position? Is it worth the jump and the uncertainty to move into a BB where there is lots of growth potential, both vertical or in different groups? Is it worth getting out of fintech now before we even know if the company has a substantial exit opportunity on the horizon? (Have equity as part of comp package)
2. Would it cause damage to my professional reputation if I went back to this HR representative ~3 weeks after declining and saying that I am re-interested? Per the company's career portal, the role is still open. HR mentioned that they have not seen a lot of people making moves right now and that they didn't have a backup candidate if I declined the offer.

Thanks so much for reading all of this. Any insight or advice you can offer is greatly appreciated.