I considered that when I was looking at it myself, but I veered towards it being a service road rather than parking aisle. If you decide to change the section where it splits from the drivethru then I won't have any qualms, though.

The main road of a car park should still be listed as a service road.

What was the purpose of deleting everything?

This post office isn't listed on the much more recent post office data (as listed on https://osm.mathmos.net/postoffice/progress/BT), should it be removed from the map?

I believe we're talking about the same way here (the one by East Link and Priory End)!

I would argue that, conventionally, parks need paths that are there solely to explore the park and not because it makes travel faster. I also think that typically a park would have benches in it to allow people to sit and enjoy their surroundings. A cursory look at way/684446905 on street view, for instance, seems to me like it's a grass area with a footpath for people to cut through (the sort of which I would suggest mapping where you can, as it means that routing software can give the fastest and shortest possible times.

Not sure if these are parks or just patches of grass, but if the latter, you can mark them as grass rather than parks for improved accuracy.

Why have you made this footpath go partially into the building?

The main roads of parking aisles should be marked as service roads - see documentation (service=parking_aisle), namely "The main way(s) on the parking lot, for entering and connecting multiple parking_aisle, should be mapped with highway=service, only."

The amount of parking spaces you had was outrageous. In total, I counted eight. While you could argue for the two adjacent to building two (way/623116760) and three, I see no reason for any of the other choices. The decision to create a parking area to the left of the service road in the large lot, for instance, or the decision to create two small parking lots on the right side of the large area, were illogical to me. Go to any other parking area and you'll almost definitely see one larger parking area.

Why would you butcher the parking like this?

As in the Geocaching user?