The UK has tight regulations on options trading for some reason. Using a good brokerage is essential, and a lot of them have lousy reviews. From experience, expensive fees can be crippling, and a poor interface can be a serious handicap.
No it doesn't, you can trade options all day every day in the UK on many different exchanges, domestic or foreign.
You might not think IB is the best broker, but it is for options trading. Hard to name another broker available to UK clients that has the same markets they offer at the same commissions.