If this is your first attempt at spriting then it's incredible! I've tried learning how to sprite countless times, and never even get close to this quality.
Mawk is genuinely just trying to help though, and even though you may have taken it as an insult, that's not how he meant it. But he's right about the bias part, we all have it for our own work. I have a close friend that I will always show my drawings to, because I know he will always give it to me straight. "This part is actually out of proportion / that shading isn't quite right" etc. I think that we miss these things having stared at the image we're working on for so long. Though for some reason, if you hold the image up to a mirror, or filp it horizontally in photoshop, you can suddenly spot a LOT of slight errors just because you're looking at it in a new light. Strange.
Anyways, this really is good work by any standards, and great work for a first sprite. Seems to me that Pyramid's head could still use a little cleaning up when he's tiliting it left or right. Particularly the fourth and eighth ones down on the right: the bottom left of his head seems like there's a chunk missing from his pyramid. Might just be that it needs a darker outline on that tiny bit? He looks great crucified though! Hopefully he stays crucified...
Also, check out the nurse's head from the back. The shading is different on the standing sprite to the walking ones. A little bit of TLC and these will look perfect!
-Silver-