Hero Unlock?

Really tempted at purchasing the hero pack. I have enough gold saved up but don’t want to spend all of it. 2 questions: how often do you see the unlock 2 hero’s pack available? I’ve spent money on other stuff..

What hero would y’all recommend at 3M Might, G5, T5.

I’m currently debating Ayrin and Thaddeus. I like to participate in COT and all the events. I have run into both problems of being capped at march distance as well as not being able to bring enough troops.

Thank you all!