I never make recommendations in these types of posts, but was surprised not to hear any other ideas on a used full size old knee mill, like the original Bridgeport Boss Machines....? I am only trying to spur the thought, and every situation is different, like portability, weight, shop space, volts/amps available, the list is endless......but I got my first CNC by buying two old Bridgeport Boss 5 machines (fully functional) for 1500 I think it was. I didn't even power them up, I completely gutted out the controls and put in a modern PC based control, and sold one of the machines to pay for the entire project. So you could say that was a hobby machine as it became a hobby type project just gutting them and getting them working with my own DIY controls.
That machine still does some work to this day, reliable old workhorse and rigid enough to make real life effective cuts in aluminum or anything. Since then, of course the FADAL is the flagship of the shop, but I love the old "real" iron, and adding the newer control was quite a fun project. I would never have time for a project like that again.
I have no experience with the smaller hobby machines.......and if its really just cutting balsa....then what the heck just do it. Have fun with the decision! You will have a lot of fun no matter what machine you get. Just hope if its a hobby level machine, you get some real productive time out of it. Hobby to me and the associated prices (I can't believe the low cost, that blows me away) means the machine itself will take a lot of babysitting as it is a hobby in and of itself.