Let's back up a bit. Dave's intentions are good, but I think he is muddying up your plans.
What you laid out as your plan in the first post is a good one. Get the 2i2, get the Oxygen 49, get the cheaper of the two mics, and get started. There is sooo much ahead of you to learn, you needn't worry about gear at this point. What you identified is good stuff and it will do what you want.
I do not think for one second that you need an interface with Midi so you can "future-proof" yourself. A waste of money. The USB connection is perfect and it will probably be the future for all Midi, anyway. If you stall out due to technical roadblocks, you will get frustrated and lose motivation to create music. If you worry about buying gear that you don't really need right now, you won't be able to afford the stuff you do need. It's a matter of compromise vs budget and you have to make intelligent decisions.
You got a good game plan in post #1, stick to it and go make music. Later, once you understand the strengths and weaknesses of your work flow, you can think about adding more equipment or room treatment.
Be sure to post up some of your work when you get a song done. Like I said, there is a lot to learn and many people here are willing to help you.
Good luck and have fun.