Assistance identifying these various mackarel’ish eocene shark teeth from the Belgian north sea coast?

[Noobductive]

Hello! Over the past half year I have been collecting shark teeth on the Belgian north sea coast from dredged sand. I have gathered the ones that are complete and identifiable to figure out specifics but the mackerel sharks prove difficult. 

Luckily I have a page with multiple species from the specific beaches and deposits I visited.

 (Onderkaak = lower jaw, Bovenkaak = upper jaw). 
 

However, this does not include all of the possible species. Many are from the ypresian, the vast majority are eocene of course. This should narrow it down immensely already. My resources are limited though. 

I have front-back views of my teeth collected and have given them numbers for easy differentiation. I’ve also tried to sort similar ones together. I think most of them could be striatolamia macrota but there are subtle root shape and tooth size differences that I have 0 experience with. I hope more knowledgeable shark enthusiasts here can help with this. 
 

I also added some quick side views to showcase that no. 1 and 11 do have a curve to them whereas most of the others are either perfectly flat or pointing slightly up (when lying down with the flatter side underneath). 
 

With eocene shark teeth ID, my biggest issue is always not knowing if tooth differences are merely related to placement in the mouth, or if they are actually differences between species. 
 

I will provide closeup sideviews of specific teeth if necessary for ID. 

Edited September 21, 2023 by Noobductive
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