By this you loose basically the biggest advantages of the software. If you filter for artists, you see them alphabetically and when selecting an artist all the movies with this artist should appear. By selecting the sorting filter you can customize the view further. I think everything you want to do is possible directly or indirectly.
Could you please post some screenshots of the library view sorted by actor for e.g.?
Either it is not working for me the way you describe it, or I am not using it correctly.
The output format of tMM is compatible with MP2, even I change settings to Kodi. Please open a thread in MP2 problem forum with your log files after import, if you need further help about it. The problem is not related to tMM or wrong fanart format.
I have been reporting problems with importer in MP2. Unfortunately, it has not gotten much traction. Currently, with "don't download anything from the internet", I see no images.