Are you comfortable with the machine you have? Is the tension truly adjustable? (Are you lucky enough to have one that uses a bobbin-case instead of a simple drop-in?) If so, don't rush out just yet for a new one. Make a few quilts first. As you proceed through your projects keep a list of features, special stitches (e.g. blanket stitch), and feet you wish you had but don't. Start dropping the loose change and loose $1 bills you accumulate into a jar or can.
In the unlikely event you decide quilting isn't your cup of tea, you won't have spent any extra money. Eventually, you'll have a list of must-have feet and features you can use to focus your shopping.
You might only need to buy a few extra feet. If you decide you need a whole new machine, by the time you figure out what you need and which machine you want, you might even have enough in the can(s) to pay for it.