If you’ve only read swamp castle, I’d strongly recommend reading more games to get a feel for how choicescript can work. Here’s a list of some: Which games are completely free on google play
There’s multiple threads around about what has a greater chance of making a game successful. I’d recommend a search of the forum to pull up some of the threads. In the end though, you can do what ever you want in HG as long as it meets the minimum requirements (30k+, passes the auto testers, nothing offensive are the main ones.) If you’re not sure how your game will be received, write a demo and ask people to read it and give you their thoughts. It’s hard to say either way how your game will be received without at least a demo.