We could effectively just reconfigure the current ones to give more stock options. Such as the Donar, instead of carrying twin SRM6's and a Large Laser, it could be reconfigured to a variant that carries a single LRM10 and Four Medium Lasers and ECM with more speed and less armor.
I suppose it's a question to the community on whether or not we would be crucified if we created new variants or "crossovers" to bulk up the Clan and IS VTOL arsenal that are not canon..
I'd actually like the Clans to have bad VTOLs. The Clans by and large don't give a damn about vehicles, especially not VTOLS. Reflecting that in the game wouldn't be a bad thing.
As for the Inner Sphere I think they have plenty of VTOLs.
