I'd love to have some of these babies to blow the sh** out of Shermans with, but like Arc said we've very low on modelers, 3 of us now I think? Could be wrong, and most have other projects as well).
Even if we could get our hands on a model for any of these, there's still prepping them for export, doing any materials if needed, actually exporting them and coding them in the editor, etc. The entire process for a team which can't always dedicate 100% of their time for one project can take quite a few weeks (assuming a model is already done, which can take months to perfect).
That's the downside of not having a dedicated studio, but on the other hand it is what makes modding fun for when you do have time to get a beauty into game!
You'll only see the Sherman (which you already know) and Panzer IV-F2, IV-D, III-J and Stug III-B (perhaps not all these tanks, but this is what we have).