Hi & welcome to the P&I forum!
In the top drawing it would look better if the skull were separated from the outline of the body of the main creature & arranged in such a way to complement the overall composition of the drawing. Umm.... perhaps top left & tilted to the same angle as it is in the whole body , just to make things clear & return the power to the outline of the creature.
Talking now about that main whale? thing! picture - you have used three shading techniques - wash, cross hatching & stippling. This practice is dodgy & is very rarely used However
you have pulled it off !
The risk with using the three techniques together is that you risk failing to balance the degree of finish in any one of the shading techniques - the drawing wouldn't work at all !
I mean by that, if you had done the wash part with lots of varying degrees of tone & made it much more subtle than the tones of the cross hatching or stippling -the drawing just wouldn't have hung together.The same is true of all the three techniques. But it does work !
because they are all balanced in the degree of finish. Well .... I would have liked the crosshatching part to be done a bit neater & with a finer pen in a perfect world .
The skull at the bottom is fine.
Kind of brave & interesting approach & subject matter too !