The tank is a great improvement, but still is a long way from being a good MODERN tank. It has added armor, better 105 gun, NBC protection. But it relies heavily on ERA, and anyone can still kill it by kicking it in the azz.
I see not much potential in this thing when fighting openly as a MBT. I'd say though, it can do a lot when fighting in the cities and maybe in jungles. In most cities, roads are narrow, so most MBTs can't pass through. This little one can, however. And it can so ambush incoming tanks. And if there are soldiers with RPGs, the 59 can save itself if given a seond upgrade with racks installed.