Suzy, I suggest you concentrate on getting all you can out of your 6" telescope for some time. I started with an 8" scope and had a great 12-15 months before I upgraded. Many people are happy with 6" or 8" for years.
BUT, you must get it out to a dark sky site from time to time to really appreciate what it can do.
If you do have some spare cash building up, investing in better eyepieces would be a good move. I suggest that you work out what you might want to have (lots of threads on this and lots of decisions) then monitor the classifieds and see when they come up second hand. Pounce and you'll improve your views. Then you carry the eyepieces to your future telescopes. Most will transfer happily.
Try to get to a starcamp. 1) Others will happily show you what your scope can do and 2) you will be able to borrow different eyepieces and see how they perform with you and your scope.
(At this point I have to admit I have three scopes, plus one coming, plus a Galileoscope or three, plus binoculars
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