Allow me to shamelessly plug our "Telespieleabend" podcast again.
If you understand German (or want to practice your listening comprehension) please feel free to check out the latest episode on Assault Suits Valken-style 2D mecha action games:
http://www.j-junk.de/videogame/telespie ... cha-games/
Telespieleabend Podcast (in German) — Ep. 17: 2D Mecha Games
Re: Telespieleabend Podcast (in German) — Ep. 17: 2D Mecha G
Sadly I'd need a time machine to fully participate, but still, love all the mecha goodies on that page! I see Meta Fight's mentioned, good call - the tank's handling and animation is as convincingly heavy metal as any good Valkenesque. A joy just watching it trundle along.

光あふれる 未来もとめて, whoa~oh ♫
[THE MIRAGE OF MIND] Metal Black ST [THE JUSTICE MASSACRE] Gun.Smoke ST [STAB & STOMP]
Re: Telespieleabend Podcast (in German) — Ep. 17: 2D Mecha G
Yeah, along with Vastar (first appearance of a mech in a game), Thexder and Finest Hour, we identified Meta Fight as one of the precursors to the subgenre. The games are more rudimentary, but aspects of all of them flowed together into the Leyons/Assault Suits formula.