I think you are.
I had been looking for an all-in-one but have recently switched to thinking about a mid-arm plus a good basic machine. It will cost more, you're right. On the other hand, my basic machine doesn't have to be something really expensive - what I have now is plenty fine - and the wear will be distributed between the two.
I guess it just depends on what you want, and how you really want to work. I like the idea of having a quilting-only machine so I never have to change the setup on my basic machine. But I have plenty of space (though not money) to make that practical.