I'm sure a tons of people have! Mine is Legend of Zelda themed that I'm working on expanding later. Currently I have a basking ledge and hides I've made for it. It's not steam punk but maybe this might give you some ideas of what you could do if you wanted to try a diy approach!
Themed hides
Themed basking ledge
Just disregard the temp readings bc they were all funky from a full cage clean lol
Those are BEAUTIFUL! Do you do sculpturing often? This is fantastic, and is exactly what I want to do with my tank in the future. Have you considered setting up an etsy shop for these? Because I admittedly might be a repeat customer if so...