I've been saving up tokens from levelling up. I've already bought a few regeneration/cooldown modules and some keys for campaign, and right now I'm level 30 with 142 tokens left. Any suggestions about what to spend them on? Should I save them? Can I get more mythicals?

i would buy regen&cooling moduels if you plan on having lots of mechs at once but you can save up for a discount and buy a gold box if you want to

The idea is very cool colors are very good hands.

I would save those tokens until there is a sale on gold boxes and then try your luck with that

If you don't feel like buying a gold box I would make sure to have 2x 21 regeneration modules (buy able with tokens).

You could also get kits, but that's not recommended.