The server is up and running. Are you playing from work / school? Maybe you have some ports blocked.

I do have plans for Shaman, Mage and an Archer

But that depends on how many people are really willing to support the game on Patreon - otherwise I have a daily job to do :)

It comes from the score.
The higher the rank the bigger you are.

Grunt can disarm mines with SHOCKWAVE
Grunt can arm mines with SHOCKWAVE

So we have stamina but it's not as frustrating as Diablo model.