Had the first service completed and a full alignment, including front camber bolts installed, at Abbey Motorsport. Immediate improvement; car has generally felt good since I've had it, but tends toward understeer, and while fine in the dry, it could feel a little nervous under acceleration in the cold and/or wet. I'd put it down to the fairly high factory tyre pressures and lowered them, but it still wasn't perfect.
It turns out that the factory spec of the cars isn't the best, and mine in particular was quite wayward on the rear - right rear had zero toe, but the left rear was toed out slightly, accounting for it feeling a little nervous in the back. This has made me feel very slightly better after my off a couple of weeks ago...but I won't get complacent. Ultimately, that was still all on me for not managing it.
Anyway, alignment all sorted and some camber added up front, and the car now feels much better. The weather is filthy today, and the roads drenched, so no mucking around, but the car feels planted and stable and the front end much more direct. I went around a wet roundabout and there was absolutely no feeling of the front wheels wanted to wash a little wide...much more confidence inspiring. And this is with the tyre pressures inflated back to the factory 35PSI spec.
Very happy now, and great service as ever from Abbey Motorsport.