There's no doubt that T-72 offers a challenge (for all the reasons you stated), but whether it's a challenge because of realism or having to bend over backwards to achieve success is another matter! I can't say I'm not disappointed in some aspects of it, because I'd like it to have more closely modeled the tank that's in its title. Some bits are great in it, the driving is cool, even if the T-72 appears to have the wrong gearbox in comparison to a real one, and the graphics are nice too, and it's also interesting that it covers a war other software developers have shied away from, but as you say, there are many frustrations with it.
If only there was a really realistic T-72 simulator. Bummer.
Chock