What I noticed is that my HOYA Infrared filter 720 nm behaves much better on Nikon D750 then D7100. First of all I haven’t seen any problems with IR hotspot in the centre of the picture. In D7100 I had quite some issues with it and this hotspot was very painful to fix in post processing. Besides this D750 exposure preview in Live view is excellent for taking pictures with already mounted IR filter (no problems with focus adjustment).
Macro lens, because it is D version of it, has not so fast autofocus. It is the problem only when you are trying to catch something dynamic. For static pictures manual focus is just the best. My previous Macro lens, Nikkor 60 mm f/2.8D, was also optically excellent and sharp like nothing else but 60 mm focal length was too small to take nice macro pictures. With 105 mm now, I have much better chances to take pictures of more fearful insects 😉