the questions, suggestions and comments were not to undermined you as speaker builder, i apologise if it came out that way.
if dynamics is your main priority, then yes go as big as you can/design allowed.
however if the goal is to have the best musical performance from the speakers holistically, then you have to consider the room and speakers proportion. One of the most important factor for me is to have the speakers disappear and just play music in front of me.
As you are going to use DSP, it will be very flexible for you to tailor the response to use any drivers combo.
while many drivers can be tuned similarly, ultimately it will have differences on how the transfer function works between the MT (on any drivers combination) and the inherent character of the driver it self (materials, magnets, combination of the soft part of the woofers and CD waveguide relationship)
my tip will be :
aim for linear response at on axis and off axis (with the correlated roll off of course)
have fun and good luck