I have tried stock froyo, stock gingerbread 2.3.4, custom andro-id 3.2 and latest vanilla roms.
I may be the only one saying this but I felt my device at its best when it was on stock gingerbread rom .
try this one at your own risk :
First you have to be running on gingerbread to flash to these custom roms
Andro -Id v3.2
Download ROM (Andro-id_signed_v3.2.zip) : http://www.mediafire.com/?nv39ja8pwrav2jr
Download clock work mode recovery(tass-recovery-cwm.tar ) : http://www.mediafire.com/?zb2xvhktd0xd7w0
instalation process :
Flashing Clockworkod Recovery (skip this step if you have clockworkmod installed on your phone) :
Open S5570_Odin Multi Downloader v4.38.exe
Select TASS.Ops on OPS Section ( The .ops file of your current rom or http://hotfile.com/dl/112245631/62ba9aa/TASS_v1.0.ops.html
Check One Package in Option
Select tass-recovery-cwm.tar on One Package Section
Press Start to start flashing
Flash Andro-ID ROM :
Download and copy the Andro-ID ROM file (Andro-id_signed_v3.2.zip) to SD Card
Reboot to Recovery Mode
Select install zip from sd card
Select choose zip from sd card
Select the new Andro-ID ROM
Select Yes - Install update
Wait till the Installation is finish
Select reboot system now
IT'S RECOMMENDED TO WIPE YOUR DATA AFTER INSTALLATION
Place these modules in /system/lib/modules/ after flashing to the new rom, without these, my bluetooth didnt work
cifs.ko.zip : http://forum.xda-developers.com/attachment.php?attachmentid=655763&d=1310746415
tun.ko.zip : http://forum.xda-developers.com/attachment.php?attachmentid=655764&d=1310746415
Need Overclocked kernel?
go to here: http://www.mediafire.com/?7shfs8938g3l3
download the update-bootxxx-id.zip
copy to sd card
install it in recovery mpde the same way you installed the andro id zip file.
It has worked for me , hope it works for you, I got it from the xda forum.
I didnt try the overclocking.