If you were predominantly a quilter, I might have some slightly different advice. For what you are doing, I think I will second PatriceJ's advice and get a lot of machine with a lot of features and when you do, learn to use the features! You've already identified some of the things you need and want. Doing bags you do need the ability for those bulky seams and heavy duty materials and some space to turn things around.
I'm lucky that quilting has been a life-long hobby for me. Way back in the late 70s/early 80s my first "adult" purchase was a fairly expensive sewing machine. At the time, it cost about the same as I think 3 months rent and other people were amazed that I would spend that much. They are other people and I don't really care what they think. For me it was a very good use of my funds and I used that machine for many hours and years.
We need the right tools for the right jobs, and we deserve good machines suited for our purposes and shouldn't have defend our purchases, especially those that pertain to a creative outlet.