I've done PCP a few times. I was doing a lot of miles for work (pre Covid) and wanted to do them in a nice car.
A few things to consider...
You don't necessarily have to have servicing done at the dealership. I had mine done at Kwik Fit which VW were OK with.
Mileage shouldn't be an issue because you tell them how many miles you want, and they calculate accordingly. I do know of people who went for low mileage to keep the cost down, but that's just stupid because they were never going to stick to it. I always take my mileage from previous years and then add a few thousand to give me a buffer.
You're not guaranteed to have equity in the car at the end to use as a deposit on the next car. I have only had this once (of 4 PCP contracts). So don't assume you'll automatically have money to trade up at the end.
I think the dealers make their money on all the extras when you take the car out (service plan, dent insurance, gap insurance etc etc). They give you the hard sell on those, but they can hike your monthly fee up a lot!
I handed my car back in lockdown (I'd done more than 50% of the contract term), as we only need 1 car now. But I'd do PCP again if life ever gets back to normal.