I think the contacts and call history stuff is hard-coded into the TouchFLO cabs so it's not likely you can simply regedit a link to use the WM history without somehow editing the code in the app itself. I could be wrong, but that's just what I can tell from poking around the registry and such.
On a side note regarding MS3.5 vs TF3D, I was actually intrigued with PointUI and a theme someone recently has been working on to mimic the Sense UI on the Hero and recently HTC Andruid devices. It looks really good and smooth. I might play with that soon and see if it does everything I want smoothly and how it compares memory wise and all that. Here's a Youtube link of how it looks, the vid quality isn't too great so I'm sure it looks better on screen, but you can get a good idea of how it looks and how smooth it is.
http://www.youtube.com/watch?v=I7C1Kpea13s