Spaceship Tylor, series II
Featuring the return of Rick Sierra, Suave Oddfellow, Space Marine Jason Voorhees, and... um, what was my PC's name again?
WWII commando hijinx like the film the Dirty Dozen or Kelly's Heroes, but with mecha in space. Can be combined with the above idea.
Take Classic BattleTech, give it a hot anime injection, and recast Kurita as the good guys. House Steiner would be classy but evil 19th century Prussian villains and House Davion as the new incarnation of the Roman Empire. Could be combined with either of the above ideas. If combined with both, then Rick and Suave get reassigned to Filthy-12, the special ops company of the Legion of Vega.
Emerald Knights of Uresia
Magic-based 1/5 scale suits saving S. John Ross's world of Uresia. Goofy heroics. Mecha that fire arrows and lightning bolts. Python jokes. Villain-of-the-week style adventures. Think MegasXLR but with elves and shit.
KamenFighters are Go!
A basic Power Rangers rip-off, but with more time spent fighting 1/1 scale opponents before combining into the MegaMekton to trash the really huge villain.
Guardians of Order's other kickass BESM/BESM d20 setting book, with an emphasis on the mecha stuff and weird science.
Farewell My Lovely Atlantis
Cherry blossoms, romance, and mecha duels in the ancient past. Last few sessions should feature the cataclysmic end of the world.
5e: Off To Hammer Rock
39 minutes ago