++1 to this.
Let me tell you story about some asteroids in an Asteroids game clone. We started that game because it looked like simplest possible game we can make and release. All was done to learn about whole process of releasing game on google and ios. Our first estimation was, about a month to code game, then week or two to release. And that silly game took us 7 months to release. Keyword here is “learn”, unless you exactly know what to do, do not expect to do anything in less than a week or so. So anybody making game for first time (or even game of some particular genre) need to learn and experiment, and this takes time. But back to asteroids. At some point i tried to make around 50 different models of asteroids. Well what can be hard about making rock in space? So i created some messy blob of polygons textured it, and put in game. All i got was ugly looking grey dot, it did not look like asteroid at all. So i googled for asteroid images and shapes, made one as good as i could. Result was again ugly grey dot. Because game was made for mobiles, so all fine details were lost and texture looked like pixelated grey mess. So i tried to make proper shader first, that means researching fake lighting models, vectors etc in material editor. Finally i got idea how asteroid for my game should be made. But making 40 of them would take me 2-3 days of boring labor. Next step was looking for tutorials and plugins (luckily there is plugin for making rocks). So after about a week of researching things I could make those 50 rocks in less that 4 hours. And I could write such story about every part of making that game. Literally every task on todo list took weeks instead of hours, because of “learning”.
So until you are EA and have whole Bioware behind you chances that you can make MMORPG in Your lifetime are low. And even for EA and bioware its not granted, just look at Mess Effect Andromeda.
There is also very serious risk when you are trying to make bigger game than you can. After 4 or so years your first models and textures will look outdated. You will play different mmo games while developing your game, so you get influenced by them, change focus and ways you want your game to work. Too long development will make your game look like Frankenstein of different quality and artstyles (artists will change or learn new skills etc), then your gameplay will look like you just cannot decide. So better try to make team willing to create tiny game in scifi setting and finish it in 2 years or so.