Speaking of Jaleco, the publisher that brought you Brawl Brothers and Maniac Mansion for the NES, has another top down shooter for the Virtual Console. The Fortress of Fury 2 would have been called Fortified Zone 2… if Jaleco ever released it overseas.
Just like the original game, you can switch between mercenaries Masato and Mizuki as they shoot through robots in a literal fortified zone. Weapons include a rapid fire machine gun, three way shot (called 3WAY), and grenade launcher. If you have a Japanese 3DS you can get Fortified Zone 2 on January 11 for 400 yen.
Since shooting is universal, perhaps this could be a future 3DS Virtual Console import?