Trikes are a total waste of time in the UK. If you have not been recently you can have no idea how congested UK roads are.
I go every year to see my parents (now just mum) and the last 4 years the roads have become more and more congested.
Even a "wide" bike makes life restrictive.
Sure there are country roads with less traffic, but usually very narrow - full of tractors or harvesters - many actually incapable of sustaining two way traffic without passing bays. Often poorly surfaced too.
What's even more fun is that UK homes have "standard" sized garages. And as cars have become safer (i.e. wider) they no longer fit in garages - so cars are parked on the roadside and this narrows the urban roads still further.
The ideal bike for the UK is a pre 1970 350-500 single.