Great photographs and thanks for sharing.
I too have been around the block with MF and wildlife. I guess we all want absolutely the best images in terms of resolution and color/contrast and in the end MF does deliver, at least if you print really big. I took my Pentax 645Z to Africa, along with my Canon and Sony systems. I also like the 'animal in the habitat' concept and it was an interesting exercise. However, at least for me the MF lure did not last very long and ever since Sony came up with the A7r3, I have not looked back.
The problem with MF and wildlife is that while you can take really beautiful photos of relatively slow-moving animals (especially larger ones), it is very difficult to do so in many other situations. For example, birds (and I like them) are too small in the frame even at 300 mm unless you are really close, which they almost never let you get, and it is almost impossible to get a BIF shot with MF. Action events, where the animal is jumping or running are also much harder, as is low light shooting which is more often than not the best image making time for wildlife.
I found that even with a high resolution sensor on an MF body, I was having to crop heavily with lenses shorter than 300mm. At the time there was really no good solution in terms of long lenses.
I was constantly lugging both my Canon and the Pentax systems to fulfill all my needs. That became too much to handle and I gave up on MF. Now I am only shooting Sony and while it is not perfect, hopefully when they come out with the longer lenses it will be close to fulfilling my needs.
Of course if one is only into 'animalscape' photography then MF may be quite enough. But if you, like me, also want to shoot birds and action it gets much harder.
The point is that while you can do everything MF does with 35mm, including environmental images, you can't do everything with MF alone and that's the rub.
Neil, would you mind sharing if your photos here were cropped at all? Must say you've got some great ones here. Thanks again for posting.