Paleozoic invertebrates from Alabama?

[Steph]

Hi! 
Looking for help with IDs & also 
 What is this type of fossil called (counter-impression? cast?). 
Specimen from Crane Hill, Alabama. 

Thanks for looking 
Pics

1-plate overview- several potential invertebrates? 

2- Potential invertebrate? Some of my newbie guesses: 

   Trilobite (side view) 

   Eurypterid- can’t  find definitive info    about if locale only had the giant type 

   Crinoid  (eg saggital view) 

   Bryzoan 

   Gooseneck barnacle- not sure when these appeared 

3- same critter, different angle 

4-other invertebrates?

5-stellate shaped imprint? 
6-another area of plate showing black ‘spots’ 

7-black ‘spots’ look angular, maybe cubic) on high power. No idea if or how this helps, but I wanted to see if it was mold (seems less likely). Included pic for fun (apologies for the quality). 

[Kane]

Not seeing any of the invertebrates you mention here except possibly bryozoan. These could also be burrows or some form of geologic mottling.

[Steph]

57 minutes ago, Kane said:

Not seeing any of the invertebrates you mention here except possibly bryozoan. These could also be burrows or some form of geologic mottling.

Ok. Thanks.  I have found several plates of burrows in this location. I was hoping this plate may have something different because previous burrows were much smaller, uniform, and completely covered the plate, but I’m sure there were lots of burrowing varieties. Does geologic mottling refer to the texture or color? 

[Kane]

I am using the term "mottling" admittedly imprecisely, and referring to its general appearance. There is also a lot of apparent pitting and staining, suggesting some weathering exposure. However, what I see as pitting may simply be an artifact of the grain size in this rock. 

[Steph]

1 hour ago, Kane said:

I am using the term "mottling" admittedly imprecisely, and referring to its general appearance. There is also a lot of apparent pitting and staining, suggesting some weathering exposure. However, what I see as pitting may simply be an artifact of the grain size in this rock. 

Gotcha.  The black speckling definitely make it harder to get a visual feel for the shapes in the rock. I read more about burrows and that ID is making a lot of sense. I’ve mostly seen feeding burrows, but if these are burrows, they would likely be resting burrows. I’m including a diagram that gave me another perspective in case it is helpful to anyone else.   Thanks for your help!