CM7, (7.03 stable -> 7.1 rc -> 7.1 stable) never tried anything else except for just a few hours to see what it was like. (miui and virtuous.)
Reasons you need cm7:
Deny any permission to any app. Is there a valid reason for an xvid player to need internet and gps permissions? HTFN! take them away!.
CM Theming engine. make it look like ics if you want. (I think mine looks better than sense with roboto font + cm ics theme + go launcher ics theme.
http://www.imgur.com/INtrX.jpg )
CRT screen off animation, this is so cool, a standard GB feature but htc and everyone else takes it out.
Apps explode/implode onto/off of the screen. Another little effect I think is standard but removed by htc.
Edge glow. When you scroll up and down a menu, email inbox, general text display etc, it has a fiery glow when it hits the bottom or top. Yet another cool android thing removed by htc.
long press vol up or down to change songs.
launch apps from lockscreen by drawing a letter on the lockscreen.
all sorts of other lockscreen things.
Power control widget in the notification. yeah all stock roms have this (theirs aren't customizable) but it's not an aosp feature, nice they added it in.
Blinking notification led actually works.
Use your phone upside down!
You can have voice calls come in as a notification if the screen is on, it'll stop your mom's incoming call from making you fail to get the power up and win the game!
Kill a misbehaving foreground app with long press back.
All kinds of settings you can change for auto backlight.
Renderfx. hooks into the video driver. With a click of a widget you can make your display look like a greenscreen terminal or all red for night mode, keep your night vision and be less easily spotted by snipers as you get the power up and win the game.
Netflix works on it! And they actually released an update to address issues with CM a prev update caused, they f'n care about us! (I think I've heard it doesn't work on some 3rd party roms, I could be wrong)
Only weird thing with CM I've discovered is you have to install flash player 10.2 and never install flash from the market if you want all flash sites to work.
Oh and there's a tiny bug with navigation. Any time you start it up you have to let it lock on to gps, after that you need to turn gps off then back on (with nav still open). If you don't cycle gps on/off one time it will lose the gps lock within 5 mins or so and not get it back. It will keep the lock (even with nav running background) as long as you do this when you start it up.
