I read this article, and while it is noticeable, West End tickets are still significantly cheaper than Broadway. On average, I was paying £50 - £80 per show. Probably the most expensive tickets for me were Cabaret (£120) and Guys & Dolls (£114). I did notice that the most expensive tickets in London are the Long-Running shows like Les Miz, Lion King, Wicked, Hamilton, and even Moulin Rouge. I guess it just depends on what the show is and who is starring in it.
The idea is to work and to experiment. Some things will be creatively successful, some things will succeed at the box office, and some things will only - which is the biggest only - teach you things that see the future. And they're probably as valuable as any of your successes. -Harold Prince