Keep everything in your hanger the same star levels, otherwise it will just put you in harder matches having everything different, so it's best just to save all resources and only rank up a whole hanger at the same time 

In addition to what Terminator said, focus on making your weapons gear stronger first (by acquiring higher energy weapons or upgrading them). That way when you do upgrade your mechs, your weapons will already be ready to handle stronger opponents.

Plarium is keeping seeker but the chances are soo low so make it like death walker 

And wht is going to be next ecr mech