Since you already own a bicycle, I'd suggest starting with what you have. Every time that you ride, make a mental list of what you like about your Sedona and of the things that you hate. Don't be afraid to tinker with your saddle and handlebar position - you can always move it back the way that it was.

If you do that for a little while, the decision to buy (or to not buy) a new bike will be easy. You will also be much better prepared to make an informed decision about whatever new bike you choose to buy.