Ideas on Ship Designer and Ship Design

I would suggest that besides the yearly intervals, the ship designer also design ships when these techs are researched

a) A new level of miniturization is researched
Medium, Large, and Massivee hull designs are researched
c) Impulse and Warp Drivers are researched
d) A new generation of weapon or defense techs are researched

Also I'd allow the ship designer to design special constructors and transports.