I expect at least a partial rescue theme with the trains too. More as it comes!
-The "Tokkyu" in Tokkyuger will have a double meaning. As rumored before, we may have a rescue type series on our hands. "Tokui"(Special Ability) + "Kyu"(Rescue/Relief)
-The mecha may be hybrids of rescue vehicles and trains. The prevailing rumor is that the mecha are known as 特救烈車 "Tokkyu Ressha" (Special Rescue Vehement Cars.)
Rumored as the following:
Bullet Train/Firetruck Hybrid
Bullet Train/Police Car Hybrid
Bullet Train/Ambulance Hybrid
These trains have the capabilities of different rescue vehicles.
They may have an origin in space.
-The Tokkyuger's team weapon is the "特急剣" (Tokkyuken), Limited Express Sword