Dan;
You MAY be "right" in saying that MA appears to largely avoid doing stuff that other folks are doing or have done... but Takom has really done some nice T-55 kits, and other mfgr's have put up several "OK" exterior kits of the type, so... it's a strong "may", with some slop! And while MA has jumped into the T-55, they haven't actually broken much substantial EXTERIOR "new ground" beyond where others have externally gone - the MA stake is really in that they have provided these superb and very replete interiors - something nobody else has offered in styrene for the T-55 and its immediate predecessors.
From that; Seeing as NOBODY has offered up any T-62, 64, 72, 80, or 90 type with a substantial interior in styrene, there appears plenty of room for MA to jump into these types with a complete interior kit - and there remains quite a bit of external detail variation among these types to be exploited to create a "newish version kit".
I'm sure that my crystal ball is, at best, cracked, foggy, and dysfunctional, but I wouldn't be surprised to see MA someday pull something up in one of those lines. Certainly, it would sell - I suspect at least as many folks are likely interested in a T-62 / 64 / 72 / 80 / 90 with a nice interior as are interested in a T-55 with such. I would certainly buy one or more of these, if they come out fairly soon (I'm getting older!).
But also, seeing as there are other companies exploring MBT kits - even of already very-frequently modeled types, such as the Panther and Tigers - with aim to provide familiar subjects with interiors... We may just be in for a pleasant surprise when someone else pops out one of these "more modern" Russians with a belly full of styrene bits! MA certainly has no sort of monopoly on being able to make up interiors!
But, hey! Only time will actually TELL!
Bob