Stuck mid-way through Root process (Samsung Galaxy S3 SCH-1535)
I'll put this here so you can mark your question as answered.

Some phones' stock ROMs automatically replace custom recoveries with the stock ones on boot, so when you rebooted to put the ZIP on your phone, TWRP was wiped away. So, simple, reinstall it.

As for a good ROMs, I use ParanoidAndroid on my Galaxy Nexus and I love it.