Okay, I haven't read through all of this yet. I read the first page and a half or so, and I just couldn't hold back any longer- I have to post...
So Mobile Shell is my interface of choice, by far. I can't stand Manilla. And yes, you want a custom ROM. Let me break it down for you...
I ran the stock ROM running mobile shell like everyone else until we had an SPL to flash. I am now running the indagroove ROM. Why is it the way to go? Because...
#1: The stock 6.1 is good, but it still has Manilla. No point in having Manilla take up space and resources if I am not going to use it anyway,
#2: The indagroove ROM does not have Manilla. Not only that, but it is WM 6.5.
#3: WM 6.5 has bigger menus that are way more finger friendly. I haven't touched my stylus in a long time.
#4: Stealth internet tethering and a bunch of other little perfomance tweaks are already included by default.
#5: You can seriously configure Mobile Shell however you want, with very little effort. No registry tweaks, no copying files to certain directories, nothing difficult at all. They made it so easy to do it just blows me away that not everyone uses it.
#6: You can easily backup and restore the Mobile Shell settings with the built in backup and restore feature. Just save the backup file to your storage card and restore it whenever you need.
#7: When you flash to a new ROM, you can keep your same, familiar interface by installing Mobile Shell and restoring the settings. So when a better version of Windows Mobile is released, you don't have to get used to it in order to get up to speed. Just install your Mobile Shell, restore your settings, and you have the familiar interface that you have been using all along.
#8: Lets face it, the biggest knock on Windows Mobile has been the interface for several years now. The underlying OS is pretty good, but the interface was outdated. And Mobile Shell is probably the best interface on the market (and gets updated pretty regularly).
Check this video out, it shows how it is:
http://www.youtube.com/watch?v=IGrfQ7IKGBs