I've decided to try Supermechs and see how I go. Any strategies that work particularly well?

Welcome ! Hope you have a great time with SM, i'm no admin, moderator or anything fancy like that, but i do know a thing or two about the game.
Best tips that i can think of are;
Don't put too much effort & money on your first mechs, You are forced to fight at level 15 after you reach level 16, so most of the lower level stuff becomes useless.
Try to buy as much item boxes as you can, as stuff at the shop is overpriced, also this is the only way to get Epic & legendary items.
Play as much as you possibly can on your free 24 hour premium account, this helps a lot.
Remember that you don't have to level up your mech at the same pace you level up your account, As matchmaking & Xp levels are separated, So if you get a great mech at level 17 for example, you don't necessarily have to let it go when you level up.. Hope this helps you at least a bit, Have fun !

Cheers mate, I'll try to remember these things.. As for the spending I may have just spent 30,000 coins on my first mech

you've made the right choice- welcome experienced battle dawner

SUPERMECHS I HAVEN'T PLAYED YOU IN A WEEK