A few things to say, here.
First, @darwindesign and I seem to have a difference of opinion about the whitelist setting. If I understand correctly, he thinks you shouldn’t whitelist anything. My suggestion would be to whitelist every resolution your TV supports - which, for most modern 4K TVs will be everything except for the modes that have a 4096 horizontal resolution. (Definitely don’t whitelist those).
If you aren’t using the whitelist I’m not entirely sure what the behaviour will be; in particular, I’m not sure if it will try to output 720p at native resolution, or upscale to 1080p. If you do use the whitelist it can definitely output 720p.
Second thing is, you don’t have to go with what Kodi chooses. Once the video is playing, if you click OK on the Vero remote, that brings up the On Screen Display (“OSD”). If you select the icon at the far right of the OSD that will allow you to manually select whichever output resolution you want.
If you’re using the whitelist and it is switching resolution automatically, and you’re playing a 720p/25 video, I would expect it to automatically select 720p/50. If you’re playing a 720p/24 video, then I’m not sure what the automatic choice is - it might go for 720p/60, or it might go for 1080p/24. I would guess maybe 720p/60, but I’m not certain.
As I said above, you don’t have to go with Kodi’s default choice if you don’t want to.
720p/24 videos are a problem, because there is no 720p/24 output mode. You might want to choose 720p/60, or 1080p/24, or 2160p/24.
720p/60 allows the TV to do all the scaling, but it will also introduce 60Hz judder - in each pair of frames, one is shown three times, and one only twice. So if you watch something moving slowly and steadily across the screen, the moment will seem to judder faster and slower as it moves.
It’s possible that the extra video processing you have turned on at the TV end (the Auto Motion thing) will eliminate the judder. Personally I can’t stand switching on that kind of processing, but if you like it, fine.
If the TV processing doesn’t eliminate the judder, outputting 1080p/24 or 2160p/24 will fix it; but that also means the Vero is doing some or all of the upscaling, which is not optimal.
My own preferred option is to output 1080p/24, then go into the Video Settings menu in the OSD and change View Mode to “Original Size”; that gives no judder and no scaling by the Vero, but it also means the picture isn’t zoomed up to full screen, and subtitles can look a bit weird. (Subtitles can be fixed, but it’s a bit of a fiddle).
If you want the picture to fill the screen, then which will look better out of 1080p/24 and 2160p/24 is hard to predict - try both and see which you prefer. And I have no idea whether you would prefer some Vero scaling and no judder or judder but no Vero scaling - that’s up to you.
So, to summarise, for 720p/24:
If the TV processing eliminates 60Hz judder, use 720p/60.
If it doesn’t, and you don’t mind the picture not filling the screen, try 1080p/24 and Original Size.
If you want to fill the screen, and the TV’s processing doesn’t hide 60Hz judder, then you might want to use any of 720p/60,1080p/24 or 2160p/24 - try all three and see which you like best. 720p/60 will scale better, but may be juddery.