P.P.
I've got the schooler's blues too. My daughter started kinder on Aug 27th and the first week was fine but after a week in an empty house, the honeymoon is over! (at least on my part).
I have been a SAHM for almost six years and her going to school everyday really affected me. I started getting this baby fever, I wanted to have another one so bad, I even looked up breastpumps, cribs and nursery items just to check what I would buy if I got pregnant.
But I made a list just like yours and you know what, after almost six years I finally got a little break to do things for me without feeling selfish since she has to go to school anyways.
I'm planning to start working again and I'm determined to loose weight so I can be fit again. My hubby wants to get his master and I want to finish my bachelors degree.
It seems your list has quite a few things to consider and I think you will have time for more kids in the future. you are so young that you could have even three more babies after you both finish your degrees.
My vote is wait but only you can make that decision it is a huge change and you will have even less time to do all these things you still want to do.
Good luck and God bless.