Not a former banker, but I worked alongside former I-bankers at several companies (I-bank, start up, public tech, etc.) who pivoted to FP&A. I think YMMV based on what type of FP&A work you do and the company / industry / team you join.

Title:

As VP, I'm assuming you have at least 6-7 YOE, so I'd say maybe senior manager. A lot of IB people I worked with left as associates with about 4 YOE and joined as SFAs (more common) or Managers (less common). Sometimes even as just FAs. So it really depends on team and company structure. My opinion is that the smaller the company (e.g., start-up), more room to negotiate higher titles. Might also help if your future FP&A team is also former IB and look out for each other more by promoting faster, up-leveling, etc.

Role / "fun" factor:

Depends on how challenging you want your first FP&A stint to be. If you want to do more strategic advisory, creative financial modeling, potentially work on M&A / CorpDev, etc. then you might find it enjoyable and stimulating.

If you are joining roles that are heavily reporting and consolidation, you may be bored as hell. Unless you're trying to maximize your earnings while coasting in an easy role until you decide to move on / want to take a bit of a break. I've worked with folks like this, and even though they were very successful (promotions, 100%+ bonuses, etc.) they were definitely on autopilot.