I've had a whole software development  career since my main work on Fractint, and of course it is easy to imagine a different project. But for all kinds of reasons, Fractint became very full featured on it's original architecture. There were some really significant ports sorted according to how well synched they are to the DOS version:

1. Xfractint, a Linux port, which was done so literally that we were able to merge and maintain it with the DOS code base.

2. Winfract, a Windows 3.1 port, that also was (mostly) kept synch with DOS. It lagged behind finally, but Jonathan got it close to synched again a few years ago. Now, of course, windows 3.1 is just as obsolete as DOS. Winfract still uses the same medium memory model as Fractint!

3. Rich Thomson's Windows windows version was an amazing port to a more modern Windows. He began with a literal port, but began (understandably) refactoring code so it was less ugly, and it forked from Fractint. Much to Rich's dismay, Jonathan and I weren't ready to cut loose from the DOS version. I'm not sure if this program ever got a following, but it successfully incorporated nearly all of the DOS Fractint's features, although it doesn't have Mouse support. If someone wanted to continue toward a modern  version still closely tied to Fractint's original features, this would be the version to start with. By the way, we all owe Rich a huge debt because through his Xmission contacts,  these mailing lists have been hosted for many years. Rich and Xmission are the best!

4. ManPWin by Paul. Pretty much a brand new program, but many features incorporated from Fractint.

There are others, such as Ultrafractal that started out as a Fractint workalike, then moved in other directions. Many years ago we answered all kinds of questions posed by the author, then he turned around and released his software as closed source.  Many of our former users love it. 

The situation is complex, but that's one view of it. Somewhere in there we raised a families and had careers! 

Tim