The T44 became a good tank a patch or two ago with the upgraded engine and gun. The reason the T59 was such a terror was that it received favorable weighting in the matchmaker and often was top tank in any match. They adjusted its weighting a patch or two ago, and it's no longer as bad as it was. No T8 tank or above really fears a T59 at this point, but it it will sure mop the floor with any T7 or below.
And I definitely agree that a group of coordinated T8 mediums is hell for the other team.
Zero damage penetrating hits are still a problem, but if you read the forums, you'll see that there was a hotfix on the Russian servers for a newly discovered bug with penetration. I don't know if the US 7.4 patch had the fix in it, but if it didn't, hopefully we'll get it sooner rather than later. Anyone loudly proclaiming there wasn't a problem with 0-damage penetrating hits really needs to hush at this point.
I've also had plenty of ghost rounds. I've always assumed it was packet loss or latency, or the generous tolerances in my Russian cannons...