Nothing wrong with SMD, most of my upcoming modules will have some SOIC/1206. It's better to learn sooner or later.
Edit: nothing stopping @Psykhaze adding 2HP to his front panel.
TPD looks cool, but shouldn't the decoupling caps be nearer to pin 16?
Without trying to spread FUD, I wonder about lots of blinkenlights in a Euro case when potentially combined with analogue modules. Do you have any data on power supply recovery when everything's humming? It could be okay with the PSU driven from the SEQ or at least isolated from the Euro rails.
For my latest work, I include a 3-pin 100mil/2.54mm Molex header with the centre pin 0V/ground and +5V on the right when the polarity tab is at the bottom of the connector. The left pin is NC. Could we consider a standard perhaps?