so yugo-made m84 was the best t-72 one could buy till advent of PT-91 and wave of modernisations in mid-90´s ?
In terms of FCS, yes. In the early-mid 90s Russia did export T-72s, which was a downgraded version of T-72B, with better protection.
IIRC Yugoslavia integrated thermal sights and even offered them, maybe Bojan knows more.
A few years ago there were news of a Croatian upgrade acquired by Kuwait for the M84 fleet, but nothing materialized.