Frankly, I wouldn't bother on making any games in RPG Maker with Steam distribution in mind.
This is a daunting task for someone with nearly no experience in game development and it can be guaranteed that everyone in the team will lose interest after a month of two. Just because To the Moon made it, it doesn't mean anyone else can.
I'm in a similar situation in terms of game making. I played with RPG Maker long time ago (2000, 2k3 and XP) and I can map, make a story and do other fairly simple tasks, but I'm beginner if comes to drawing, I can't compose music or program in Ruby.
Frankly, if I were you, I'd wait till RPG Maker team will make an iOS/Android wrapper (as they said they're working on it) and make some short (few hours long), but playable games for iOS and/or Android and distribute them for free, and then move to more advanced projects. I'd forget about monetizing it (even for 0.99 of currency per copy) if you can't write some custom scripts by yourself (especially that have something to do with battle system), make custom sprites for playable characters or compose some music.
For me, using RTP resources won't make your project really serious, unless they'll just serve as placeholders.
