I guess most of us like what we are used to.... In which case (now don't laugh) I should recommend you look for a secondhand Frister & Rossman Cub4 from the 1970s.
Seriously: When I have saved up enough money for a machine with a few bells and whistles, I'll plan a proper 'campaign' during a holiday. I'll prepare a stack of small projects at home, the type that need all the sort of thing I either normally do on my machine (decent invisible appliqué) or would love to be able to do (very small machine blanket stitch a la Bernina). I'll then phone the dealers of several machine makes and arrange for me to go and test drive their machine. I will take as much time as I feel like, and I won't be pressured by over-zealous sales people. I'll then go home with my test pieces and a ton of written notes, sit down, look at everything, read everything, and then...... yes, you got it.... buy a machine that'll hopefully prove to be a marriage made in heaven.
Until then I listen to what my quilting buddies say, and I love workshops where machines are provided (a sneaky test drive), so when the time comes I may not feel like having to 'hit' every single make of sewing machine that exists.
And they better convince me that their after sales service is superb!
Laura, I keep my fingers crossed that whatever you decide will be just right for you.