If you want your tortoises to have a nice view of beautiful architecture, vote Cotswold. 
But this time, despite good indoor areas I would class the following as substandard outdoors :
Colchester
Crocodiles of the world
Twycross
Probably Bristol and London too!
I said probably, I should have said possibly really, because I couldn't really remember it that well but it never stood out as being particularly impressive.I am curious what makes you say that Bristol has a substandard outdoor exhibit?