So im Coming from a complete gamer background myself! I have always had a great passion for video games and have played them from a young age…i am now at the age of 26 just deciding to venture into the game development space and it has been nothing but exciting! i would really love to join onto a large team of devs or even a dev studio. I would love to build a RPG MMO myself! I definitely for see manyyyy complications of which i couldn’t even begin to think what those would be other than cost of servers and just assets alones! but in reality i think i really want to make a fun Real time session games for my friends and i to enjoy together i have a lot of friends in the streaming community so it would be really cool to create a game that maybe interacts with twitch in some way to help bring the views in as well but also allows streamer to play together and have their chats integrate challenges into the game or maybe be able to give their favorite streamer an item via channel points or something that could help that streamer take down their other streamer friends that they are playing against …so almost like hunger games where each tribute has their supporters on the outside that sponsors them gifts that help them in the game to possible win where the chat would be the sponsors and the streamer is the tribute 
MMO is a great ambition. But good plan to work your way there with some session based games first. I would tweak the plan to build an MMO as part of a team, as that’s much more doable!