Is that your entire roster, or just a selection you want us to focus on?

Either way - Coldheart, Vogoth, Khatun, and Jorrg are all excellent choices. Personally I would stop with Warmaiden - leave her at 50, I don't think you need to bring her to 60.

Which of the four you choose is probably more based on what your focus is than anything else. I would do Coldheart/Jorrg for dungeons, Vogoth for CB, and Khatun for arena - but realistically whichever you choose to take to 60 will be on every one of your teams until you get a better replacement.

Jorgg and Vogoth would be the two I'd pick from. Vogoth you can definitely use anywhere and everywhere. 

I agree with everything above as well.

Vogoth, CH, Jorgg I agree...I would also like to add Aox to those worthy of being 60...

Thanks for all the answers people! I am going to start working on Vogoth since I feel like he's the most versatile and perhaps Coldheart afterwards, since I heard many good words about her!