Definitely liking the pick, I wouldn't change it to a hammer.
The lucern hammer idea is a good one.. yeah they were used in the middle ages, an anti-cavalry weapon.
Perhaps the delgon heavy infantry would have a few of these pole-hammer soldiers attached to them, staying behind their shield wall, so that if cavalry come close, they can be used against them... a fun addition would be to give the lucern hammer a hooked back, rather than spike, like a bill-hook, so they could try to snag & drag a rider from his mount and the heavy infantry could then attack them with their battle picks
Could make a nice opportunity for a militia captain's specialized skill.
For the knight, the armor details & padded barding are looking great.
For stirrups, rather than regular stirrups (which would obscure the fubarnii's cool feet, what about a wood pedal, kind of like a thin bike pedal? it could be 'L' shaped, coming out of the bottom of the padded barding, probably connected by a "Y" shaped leather strap that runs under the barding which connects to the other side's 'Y' shaped leather straps going down the other side .. not that the detail of it would be seen, but fun to know how something works anyway