If you want to completely re-vamp your phone into something else, you might want to give MIUI ROM a try, this ROM basically strips TouchWiz UI completely and puts a new MIUI user interface.
I’ve used MIUI ROM on other Android smartphones before and I have to say this is the best ROM if you are a theme-switching addict. The ROM comes with a free theme switcher with hundreds of free themes that lets you switch themes on the go.
Try this ROM and let me know what you think!
Download ROM here:
Download MIUI ROM
Donate to original developer here
Don’t know how to install a new ROM? Look here.
Don’t forget, you need to root your Galaxy S2 and make a backup of your ROM first before installing new ROMs!!! Also backup apps!