To me, the weather is a huge bonus, but I am in the South-West, the weather is wonderful at the moment, but even when it is not hot/grey and rains a lot, it's functional- you aren't too hot, aren't too cold, don't have to go through snow, or have the air con on constantly. I spend a lot of time in a Mediterranean country and it is too hot for me and don't feel at all productive.
I also dislike a lot of the things about the UK that others have mentioned, but I'd also say that these have got worse in the last 10 years. The roads did not used to be full of potholes. Rubbish was not as prolific on the sides of roads as it is now. The homeless population which is very visible and shocking in the Uk is growing again, ditto drug use. Public parks used to be immaculate- I have pictures to compare and they are now untended and neglected looking. People respond to this downgrading of their environment and I think the street culture in the UK (as in what it's like to walk around everyday) is quite rough and unpleasant at times. Calling out to women is very common, whereas in the country I know best in Eastern Europe, this simply doesn't happen, even though in summer half the women are walking around wearing bikini tops near the beach.
The positives- despite everyone feeling lately they live in a police state, they really really don't, I haven't seen any police during lockdown except in a police car. People do as they please a lot of the time. People dress how they please as well, in lots of European countries, how women dress is very much judged, it might be judged here but that doesn't stop anyone going out in a strappy top and see through leggings. If you have tried social mobility in France, the Uk does not look obsessed with class! Or try being Roma in most of Eastern Europe.
One of my friends loves the bureaucracy in the UK, she comes from a country where the law is applied very randomly, or rather, there's a lot of bribery, things also take years which here are relatively straightforward. She likes the fact we are all stuck on the same government website whereas at home it all relies on being prepared to pay bribes or be massively frustrated.