What should I put in this?

75 gallon (48x18x21), bioactive w/ powder blue& orange iso, springtails, worms, fully planted-not a single fake, been up and thriving for 3+mos Has space to accommodate a 12in water feature &filter if needed per species.

I love it and I am just stumped on what to put in. I’ve considered a red eye croc skink? Leo gecko?