Assuming that this question isn't asking for views on authenticity (as I don't have the expertise to weigh in), when you say the space between the prongs, do you mean the gap between the stone and the beading? That does occur - more experienced folk can correct me, but I believe more obvious gaps/air lines are not uncommon with older MOP pieces. Also remember seeing an interesting view somewhere in the forum that the air lines in newer pieces may be intentional to allow the material of the motifs to expand with temperature changes, as the gold and the stones would expand and contract at different rates. I can see gaps/air lines in my fairly new 10 motif if I hold it up to the light, but I don’t notice them when I’m wearing the necklace so it’s okay for me. If I could see obvious uneven gaps when I’m wearing a piece, that’d likely bother me. So perhaps consider whether the air lines are to the extent that they will bother you every time you look at the bracelet. I'd want to be able to look at my piece and enjoy, not feel disappointed or annoyed.
And when you mention that each motif is different, I can't immediately tell from the pics, but with something like malachite I'd expect (and want) some variation in the striations given we're talking natural stone. Again, perhaps consider if the appearance bothers you.
Not sure if this is what you were getting at, but hope that helps to some extent? Sure the more experienced folks can provide more/better advice!