Looking at it it, seems like a nice little tank.
I would say the bigger the tank the easier time you'll have. Water paramaters don't change as quickly. Imagine your salinity if a gallon of water evaporates from a 12 vs a larger tank. (12 gallons limits your fish options, I had a 12 gallon that was quickly replaced with a 24 gallon) After a move I got a 50 gallon with sump.
I would also be hesitant with the lighting. I'm not sure what it has, but lots of time people end up finding a need to upgrade the lighting.
Not saying it couldn't be done but as a starter tank you might be hating life. I would recommend a Solana if you are ok with the possibility of light leakage (light leaking into room, my small tank was next to my couch and light leaking while attempting to watch a movie was not acceptable) If that is a concern I'd steer towards a jbj Nanocube 28.