Silvia really work on making more ROUND shapes and less hard edges. Try using the Sculpt Surfaces tool or the Artisan tool they help out a GREAT deal when working in NURBS. I usually start out by having my MAX displacement at a low number like .015 then go up from there. I find that the SMOOTH tool is my best friend =).

As for seams and Such i reccomend playing around with the stitch surfaces tool also fillets help when tring to hide a harsh line crated by two NURBS pieces placed together.

I really reccomend taking a look at how this dragon head was PATCH modeled using NURBS.

https://www.highend3d.com/maya/tutorials/patch2/

it's coming along good. (stay away from green i liked blue better)
Oh hey i found that the best resource for animal eye textures is a TAXADERMY SITE lol as creepy as it is i got good quality LARGE eyeball pictures of over 50 animals.