WTF correct care?

[Bluez3023]

I've read a bunch of care sheets but I have a couple of questions connected to the pictures I'm sharing.

1.) Both frogs (Hermes & Icarus) were the same size when I first got them and one of them have gotten a lot bigger, I've seen both of them eat (dubia/mealworms) so I don't know if something is up, Is the smaller one not eating enough or is the big one eating too much?

2.) I have them in an 18x18x18 exo terra, should I upgrade them to my empty 18x18x24 tank yet? or should I wait until they are larger and save the tank for something else?

3.) Should I stop feeding them mealworms, Ive been switching weekly between mealworms and dubia. Does variety even matter? I would prefer not to deal with crickets but its an option.

Thanks for your time.