It sounds like you're not gonna have any problems with Tokays as they're one of the most durrable lizards I know of. That being said they can survive just about anything but can become incredable captives with a little more.

Cage size.
I think a pair could be comfortably housed in a 2x2x3tall. If you have the means they won't mind as big as possible. I think 2x3x6 would be awesome and you could certanly keep a trio. Blakes right I would vent it on the top somewhere and somewhere lower down to keep some circulation. Pothose are about the best plant you could use and would hold up to a large active gecko. search "safe plants for reptiles" and you could use just about anything.

Growth and reproduction.
I have personaly raised numerous tokays to adulthood and it takes about 1.5 to 2 years from a baby to a "fully functioning" adult, around 8". I have fed tokays suplimented crickets thier whole lifes and not had any problems. I currently feed suplimented crickets and dubia roaches. When raising young I feed them as much as they can eat and keep them in the 1x1x18? exoterra. If a female is not old enough and is constantly laying eggs she will run into calcium deficencies. Make sure she is of good size and healthy weight.

I'll post more latter as I have to make it to a ski movie now
Nate