Some random thoughts, subject to the disclaimer that I'm not a financial adviser or anything like that -
Defined contribution schemes will perform differently over time - you might consolidate in one that does better than average, you might not. Are some charging higher fees than others? Do any have fees for transferring out? Consolidating will simplify admin, and might lead to lower charges, or it might just mean you're paying X percent a year on a higher amount rather than about X percent on a few smaller amounts.
Some defined benefit schemes will allow transfers in - I went (back) in to local government a couple of years ago and the estimated (broadly guaranteed) pension at retirement on the transfer value on a few DC schemes I've picked up since I left local government was on average 40 - 50 % higher than the estimated (not guaranteed) pension if I'd left them alone, although it's possible the estimates were over-cautious and I might have done better staying with them.
Your scheme may not allow this, or may have a time limit on doing so (I think I only had the right to transfer in within a year of starting.)
Transfers in to DB schemes might 'buy service' as in will add the equivalent of X years' service to your pension calculation, it may just be that X pounds paid in will get you Y amount more pension. (the latter is how the local government scheme works now - it used to be a case of buying service, as happened when I first joined the pension scheme and transferred something else in, but that was in the early 90s.)
Some DB schemes allow additional payments in to the main scheme, either on the basis of buying service, or buying additional pension either as a lump sum or X amount per month. Some places with DB schemes offer an 'additional voluntary contributions' scheme (either only offering this, or offering it as an alternative) but this behaves like a defined contributions scheme. This may or may not be better than your current DC scheme/s and may or may not allow transfers in.
https://www.moneyhelper.org.uk/en/pensions-and-retirement/pension-wise may be worth a look.