Nah, not really.
While I appreciate your perspective given your situation, only having one side able to honestly comment on the situation is hardly the best. I've dealt with dickish buyers enough that I'd love to neg them and they would have deserved it. But there's no option for an irresponsible buyer. Three weeks to pay then leave comments to the extent that shipping was slow? Seriously?
I 100% agree with you - I am a firm believer in if you win an auction, you pay immediately - I always do. I bid and paid on this item in question within minutes - normally for me I take advantage of Buy-it-Now and do it at the same time. In this case, I had to wait for the auction to end since there was no BiN.
Also as a buyer - I rarely care about shipping speed - if I get a tracking number and can watch it's progress - that's good enough for me - if it still hasn't been shipped 2-3 weeks after I've paid - that's when I get concerned and probably from that seller's perspective - a bit dickish.