I love my new VZW GS4, but the biggest thing I miss is Halo as found on some other ROMs that were available for my Galaxy Nexus.
It is way over my head to get it ported, but I know someone out there can do it. In an effort to entice them, I am starting a bounty thread for us to offer up donations to whomever can get it done!
I'll kick it off by offering $50USD for the first person that can provide a TouchWiz Halo-enabled ROM.
EpicDraws - $50