@Oreo2019 - I’m afraid I have no experience of Tiffin, so it’s hard to compare. LU is a very buzzing, fast-paced environment and I would go so far as to say the teaching and curriculum are inspired. On the other hand, it’s quite easy for a child (particularly in the younger years) to feel a little anonymous. It’s hard to stand out for anything if you feel “known” in a school like that. I can only compare to G&L which has a much more “containing” vibe, if that makes sense (eg. they go and see the head for a good piece of work, etc - LU would never do this).
I wouldn’t say LU is inclusive where drama is concerned, no. It’s a big school and many very talented actors will never get a part, so they give up after a couple of years and do drama outside instead. There are many fantastic things about the school, but I wouldn’t say this kind of inclusiveness is one of them, sadly. Hugh Grant went there apparently, but never got a part in a play 
Although it’s not the most nurturing school to begin with, the good thing is that, by the time they reach the upper years, it’s fantastic because they really thrive on the open, busy co-ed vibe there, which at times feels more like a college campus than a school. The school is very diverse, liberal and forward-thinking. Although obviously academic, it’s not a hot-house environment - eg they don’t even put grades on reports anymore as they would rather students focus on the teacher feedback to improve, not just a number.
Another distinct feature of LU is the “activities week” every June, where the whole school closed and they all go off on residential trips, anywhere from Devon to Morocco. I’m probably not the best person to comment on the sports tbh, but the sports centre there is quite new and like a health club. Fantastic facilities for swimming and rowing in particular. Hope this helps. Good luck whatever you decide!