Your set-up is pretty, but you may think about safety and the frogs needs first. Perhaps a second tank for the fish would be safer. Make the water shallower to about 1 1/2" or less and add more plants and maybe a large rock to climb out on. Take a peak around the tree frog vivariums. You're sure to get some great ideas .

If you're concerned about crickets as feeders, a good guideline is their food should be no larger than the distance between their eyes. You can order smaller crickets online at joshsfrogs, greatlakes horned worms and a few other places.