Merge blocks can't connect smallship to largeship, they only join two same-size grids into one with the ability to detach.

Regardless, they won't lose their gliding ability if you connect them via rotors or something like that.
They will kinda act differently because the forces are applied to center of mass but since rotor heads are a different grid, the center of mass of the rotor head grid is what it will be applying force to.

Ok thanks

Would this work with connectors instead?

Yes, what I said above should apply to anything that can physically link two grids :P

Sorry, didn't catch that there haha. Thanks though!
Great mod, too! Keep up the great work!