Plastic tubs are used mainly because they are cheap (relativly) easy to keep clean and provide all the basic needs to the inhabitant.
Granted I'm sure there those that frown on tubs due to the same points you mentioned but I myself have never had any negative side effects from using the plastic tubs in a rack.
Exactly the oppisite my BP's did better in the tubs/rack than in traditional caging. Partly due to the fact that most BP's are elusive in nature.
There are always the taller tubs and one could even add branches and decor but I think that is getting away from the idea of the rack in the first place.
Chris H uses the taller CB-70 with great success so maybe he will chime in and share is view.
As far as Heating and Humidity both are really easy to control in aplastic tub/rack situation. I myself heat the one end of the tu to the hot spot and situate the water bowl so that it creates the humidity. Situational misting adds what is missed by the evaporation of the water source.
As far as stress the opaque tubs provide a sancuary from the hustle and bustle that is the reptile room.
But to each their own.
My 2 Cents
Jeremy
I use traditional caging for larger animals.

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