Big tanks are fun but nanos are just as enjoyable imo. Some of my most favorite best all time tanks people have made are nanos.
Get what you want and can legitimately maintain or you will be downgrading. There is a group who wastes money cuz they didn't go big enough and another who wastes money because they went too big.
I am setting up the Seapora 80g and the 16 height is of no bother to me. Why should it be? My 20gs are only 12 inches tall and they never caused me any issues so why would 16?
I am actually following your build. You have that awesome cat.