He didn't leave much behind. Not in terms of quality. He was in lots of films but few of them were good- and few of them offered him a starring role. The Shakespeare movies, Hitchcock's Rebecca, The Entertainer, Spartacus- these are the career highlights. And the Shakespeare performances are really just the record of big, fruity stage performances. That goes for The Entertainer too. He was good in Rebecca but Cary Grant would have been better and he was good in Spartacus but it's Ustinov you remember. He did quite a lot of TV in old age, but nothing wonderful. Did his cameo performance dominate Brideshead Revisited? No, it didn't. John Gielgud- another fruity, old stage actor- puts in a teeny-tiny appearance that's a lot more compelling.
Was he gay? Lewis doesn't think so.