Ten years isn't really that long in terms of the investment profile and planning permission, funding and animal acquisition that would be needed for Twycross to be the best zoo in the UK.
It's nice to see it making some changes and there are some good green shoots, but at the moment it seems a deeply average place even though it does have a number of unique species and a couple of really good enclosures. I admit I am not a fan because the visitor behaviour on my couple of visits has been stand out some of the worst I have ever seen and it put me off making it a frequent destination. That's probably untypical. I do keep meaning to go back but it's not quite enough even with a couple of things like Bonobos you can't see often elsewhere.
I welcome any improvement in a collection, the more high standard places with amazing exhibits the better though. Will be interesting to see how it moves beyond being a mixed bag of OK, good, sort of ok, great and not great.