The shark has a couple of dependency oddities ... the forehead piece does not depend on the eyes already being in place (making the eyes impossible to insert if it were a physical object), the same with the hidden one by two flat white piece under the rear back of the shark (between the dorsal fin and the tail on top)... this piece is very difficult to select however since the side pieces are zigzagged there are little triangles of the flat white showing if you look upwards into the space (and also use orbit and smart cull - top-right buttons!)
I don't know if you used "Smart cull" to do these models but I highly recommend it as it was recommended by DasMatze and made a world of difference for me; though I will admit it can be confusing on larger models with lots of repetition in different orientations or models that require some working down from the initially built block, rather than the standard working up only (some of the older vehicles often, partially, work down, weirdly).
Other than that they look great and were really fun to do... not sure I agree with the turret's stand due to it forcing a slow start to building the model but I guess I've got a lot more perks now and it wouldn't be noticed by people just starting out! (I really recommend the inventory upgrades before you try the Pet Shop! ;)
Have fun :)
P.S. If you are okay with me putting your models onto the github (with attribution of course) do you happen to also have the ldr's they were made from?