I am leaning towards a 6-seat configuration to provide another method of 3rd row access - but it's interesting to hear that the seats are a bit slow. I wonder if that's something that could be worked around with a software tweak - not the motor speed, but some way to signal to the fob (triple click for instance) that you want the doors open AND the 3rd row exposed. Both the door and seats could start moving simultaneously, earning you a little time.
Yeah, if I knew I wasn't going to need 7 seats from time to time, that's what I would have done - just gone with 6. The middle seat is a bit compromised in that you can't sit there and use the second row cup holders at the same time. I haven't seen a 6 seat config, but it would seem to make sense that you'd have good access to the third row without the middle seat.