we have atleast three types of tanks running............ this is not heavy tank so not justifying adding another type. unless AK2 was not a hit. This is like buying a camry while you already have an accord.
There are many obsolete types(Type-59, Type-69, Type-85 almost 1000 in total) which need to be replaced. A heavy tank cannot replace all these tanks, even the worlds advanced armies like germany,france, Uk etc are operating their heavy tanks in quantities of hundreds only, not thousands. The heavy tank can be opted when all the other tank inventory is filled with formidable AZ,AK versions and VT4.