[Snowflakian]

Inhumanoids.
Would love to see them updated alongside a 10 years later series that introduces new streamlined more agile tech for a new generation taking over the mantle under the tutelage of the originals as well as more creatures new and old. Of course, make it a 3.75'' toyline compatible to MU and modern GI Joe. This will help make the big creatures tower even more so. Combine elements of Bubblegum Crisis hardsuits to the new gen, but keep the originals iconic and similar for nostalgia's sake. (Helps for in show jokes too, cause you know Auger would never quit complaining about it or comparing the tech's durability.)

Rocklords done similarly as Thundercats was as an all new re-imagined line and series including a special vs Gobots(also reimagined) 90 minute special. Would pair up nicely to the originals as Gobots had the series and Rocklords had the movie. This time it'd be reversed.

Centurions. Complete update and re-imagining with 3.75'' toyline alongside booster armor set enhancement packs.

Silverhawks. Complete re-imagining and 3.75'' toyline. Take some design cues from the redone Darkhawk origin with the Fraternity of the Raptors stuff even.

And that's about all I can think of.