Given that wave 4 on 2.0 is coming out with a small base silencer, with all the identical cards from the conversion kit, what will this do to the medium base silencers from 1.0 that one might have upgraded with the conversion kit?

Is the Wave IV model smaller? I sure hope so!

Regardless of the size of the model, every version of the Silencer is a small base ship. The tokens in the conversion kits are for small bases, just like First Edition and the Wave IV release (there was no medium base in FE).