You must be running a internal gear hub in the rear, correct? I can't see how you could spin at 30 mph for 44 miles with that tiny chainring, and a normal 11 tooth cassette high gear in back.
I suspect your buddy's Stokemonkey wouldn't do any better than your rig. Hills take a huge amount of power.
Your mid-drive idea, with a geared hub motor has me sold. I will contact cell_man about a motor...maybe this one.
What is the highest amps you are pulling? Sounds like this motor is limited to about 15 amps.
No internal geared rear hub. Just an 11-34 cassette. My bottom bracket is a Schlumpf high speed drive. http://www.schlumpf.ch/hp/hsd/hsd_engl_ausfuehrungen.htm It's an internal geared two speed bottom bracket with a 2.5 overdrive. The chain ring is 27t and in overdrive is equivalent to a 67.5t chain ring. That gives me a gear inch range of 20.6"-159.5 with a 26" rear wheel. A pedaling cadence of 80 RPM will get me ~32mph and 100 RPM would net me 40 mph.
My e-assist is not a mid-drive but a bottom bracket drive. The motor see all the gears and not just the back set. My motor controller is/was 20amp. The Mac geared motor you linked to looks close to the specs of my Crystlyte direct drive motor but less weight. With the right setup, I think you'd be happy with it.
Here's the E-S link from May 2008 http://endless-sphere.com/forums/viewtopic.php?f=3&t=4426