Thanks for the feedback. This particular feature is not planned because the goal of Transmutr is first and foremost to import 3D models into SketchUp quickly & easily.
We chose to include geometry simplification because SketchUp suffers from poor performance when opening complex models with a lot of geometry.
In that regard, adding a subdivision feature would be quite counterproductive
More generally, we chose not to make Transmutr an all-purpose tool that wants to do everything, from modelling to texturing, since there are already great 3D software packages out there that provide such features