Yeah, we never bothered adding a re-labeled DM53 duplicate because it seemed rather pointless. But, some customers wanted it for cosmetic reasons so we complied since it didn't cost much effort in the first place. The DM73, well, we decided that we wanted to keep the update installer at a reasonable size so it was removed at the last minute. Again, it's a DM53 with a few more percent of performance squeezed from the existing design. Since it hasn't yet been fielded and won't be before the end of the year, while it's a bit sad that it didn't make the cut I think that the difference is not so dramatic - except for a single relevant case within the Steel Beasts vehicle zoo, and that is Armata frontal hull hits.
But you can expect it in one of the next updates, though maybe not exactly the next one. It appears likely that we'll have to take another round with the patches because of the performance loss with some smoke situations and then one or two other things as well. But whether it justifies blowing up the patch size massively for a the addition of a single round type is a question that we have to solve internally.