Corporate Development - worth the paycut / lateral salary move (london)?

Hi guys

Background - Big 4 Audit followed by close to 3 years in Strategic Finance Analyst role in leading corporate. Currently on 60k PS and most likely going to get bumped to 65k in Dec but high chance to 70k & promotion to Manager role.

Exploring Corporate Development opportunities. Have had interviews for multiple manager / analyst roles at 70-75k however despite positive feedback miss out to ppl with T/S or traditional banking background.

Some roles that recruiters have approached me with from SMEs / several hundred m turnover companies are on 55-60k. Is it worth taking such a side ways / back wards step salary wise? I really want the move but i'm getting loads of opportunities for traditional FP&A manager / FC roles at 75k +....assuming i take one of these 55-60k roles im wondering whether after 1-2 years i'd still be getting the same 75k roles meaning id have missed out on maybe ~30-40k PS pre tax salary (assuming that if i moved to a 75k FP&A role id be on track for an 85k one by 2020)

What would you do in my situation? Many of these FP&A/FC type roles are heavily involved in the DD / Integration / Carve out process which could be used as a stepping stone to a more traditional transactional involvement later on i'd assume.

I imagine that part of the issue is that some of these roles are aimed at Analyst 1/2 type people who are probably on 50-60k base & 100% bonus in banking and are happy to be on 60k & 10-15% bonus for lower hours in their 3rd year out of uni...but for someone 6 years out it seems to make less sense imo?

Many thanks for any advice

Regards