Hello there. Just wanted opinions on what I have done.

Yesterday, I did the speech, and sneak and a little bit of Restoration power-leveling? I am level 57, should I start again? I didn't want to cheat but...

Anyway. Flame away!

It's a single player game so if you're happy great. Post-level 50 it really doesn't matter. Nothing is going to get any harder. If you get things done at level 50 you'll do things about the same at level 81 (or way easier if you use certain perk/skill combinations). After level 50 what I do is start diversifying my options. For example I got to 50 this time using 2-hand, heavy armor, sneak, alteration and block mainly (I love Ebony Blade sometimes). Of course some speech, restoration, lockpicking, smithing, enchanting, and pickpocketing happened along the way. Post-50 I focus on opening up the option of using 1-hand weapons, conjuration, destruction, etc...