Quoted By:
While we wait to see what Hasbro has in store for the second wave of Retro Zords (assuming there is one) here's everything I have from Bandai America which scales well with them.
In Space are micro playsets, Wild Force through Dino Thunder came from adventure sets, the Supertrain is from the intermediate Zord assortment. He should probably be bigger in relation to the Megazords, but his size varied in the show from huge to barely taller than the standard Megazord, so I think this works as a good middle ground.
Things I tried which didn't work. Turbo Megazord micro playset, looks fine compared to Lightning Collection villains, but too big next to the Retro Zords. Lightspeed Solarzord micro playset, too small, more in line with Bandai's standard 5" action Zords. Hurricane Megazord adventure set, too small, it's technically the same size as the others, but because it's a 3 Megazord combo it's better scaled with the 5" action Zords. RPM adventure set Megazords, too small, sometime after Dino Thunder Bandai downsized the Megazord figures in the adventure sets to 5".
I doubt many people still have this old stuff (if they ever did), but figured I'd put it out there for anyone who may find this info useful.