Wroclaw zoo's legendary reptile house is often regarded as one of, if not the best, in Europe. See this mouth-watering species list: On-show species within the Reptile House - 26/09/2024 [Zoo Wroclaw] - ZooChat
Krokodillen Zoo in Denmark has all species of crocodiles. I haven't visited, but it is on my wishlist.
Servion Zoo had the largest Komodo Dragon and Siamese crocodile i've ever seen and a nice collection
Furthermore i personally prefer reptile exhibits to be part of a ecodisplay like the watermonitor and reticulated python exhibits at Burgers Rimba for example.