Its software engineering anything at all can be done, but it is ALWAYS a case of effort required versus benefit, and there are TWO developers working here, part time, volunteering, and they have said, this would require a major rewrite of a large chunk of the game because it is hard coded to take secondary slot 1
and no, they haven't commented here, but they did (both of them) in the Tanker changes dev threads where they were working on changing the starting slots as part of the tank rebalance