Corporate Development -> Corporate Finance

I have an opportunity to move from corporate development (M&A / strategy) to corporate finance (FP&A and IR) internally at my midcap tech company. For the last year or so, I've been de facto leading the latter function (takes up to 70% of my time some weeks). During my formal annual review with my CFO and my manager, they brought up the opportunity to formally switch.

I have been in corporate development my whole career, though we've often touched FP&A / finance to some degree. Have been at highly acquisitive companies and raised a lot of money, etc. I am one of 2 number 2's (other guy is a step more senior) to the head of this group. Sticking with the role, comp would be flat at around $300k. Career progression is just to keep doing deals, keep getting bigger - maybe one day switch companies, or try for PE / VC when I've got a long deal sheet and have a strong banker / referral network.

The new FP&A / IR role would be more of a promotion, potentially to a VP-titled role. I would be n2 to the CFO. Same responsibilities as I have now, but also with some additional ability to drive the direction and buildout of a formal corporate finance organization. A lot of things to potentially do there around setting up reporting, etc. that I've often talked about. Comp would be a little higher, but likely less that $400k. Next few years would be building the function on the ground floor, and as we grow, likely have a team of 10 within 5 years. Maybe CFO of a small company is the next step after that, or another VP role at another company.

I really like corporate development and have not really ever thought of myself as a corporate finance lifer, which is what the other job would lead to. Frankly, I don't really care about the money that much either as I'm more than comfortable. Currently leaning against taking it, but welcome thoughts from anyone, especially if they've made a similar switch.