I think I'm going to go against the grain here and suggest that you go ahead and fix the bike. You have been happy with it for 3 years and like the riding position.

If you choose to do longer rides, chances are you aren't going to do them very often so you will be going through some discomfort on the long term for a gain in efficiency that you won't use often.

Now it should be noted that I think "comfort bikes" like the Cypress are horrid. When I got serious about riding, my wife and I started on comfort bikes, specifically the Specialized Expedition which was very similar to your Cypress. Then we went to road bikes, and that was a move in the wrong direction for her so she went to a recumbent. The disparity between me on a road bike and her on the recumbent made it challenging to ride together, so I've recently gone to a recumbent as well.

We tend to do longer rides as a rule, so our goals were different.

You can build on your miles with your bike. I did a metric century on the Expedition and it was brutal, but at least you'd be starting with something you already like.