But, but the audiences would have been too stupid to grasp that Data has an evil twin built by Dr. Soong and disassembled by the crew. It was easier to grasp that he has a stupid twin built by Dr. Soong and disassembled by Romulans.
The audience would have been to stupid to get that Picard has a little bit of history with a Romulan Admiral. It was easier to get that theres a Romulan Commander he has no history with.
I think Tomalak would have worked fine, but would have preferred Donatra over Sela.