Question [Q] Rooted a while back - what can I do now?

I've been using the phone since I rooted it pretty much the day after I got it. I'm still running touchwiz and would like to flash something that is far lighter, removes bloat, includes ability to use hotspot and just runs faster. I've not done much of anything besides confirm root. I am familiar with most of the terms and not afraid to get my hands dirty.

I will need some easy-to-follow steps if at all possible. I'm in need of being able to backup apps, contacts, data/pictures/etc before I flash anything (I assume I will lose all of them). I'd love recommendations on a good ROM to suit my needs too. I guess I'm feeling a bit overwhelmed and not sure what I can do and then exactly how to go about it without losing anything or bricking my phone.

current build: I545VRUEMK2

Thank you in advance for your patience and help!