Yeh all issues.
T67s, many of the tier 4 TDs, and the derp guns are all problematic at those tiers IMO, the HP boost will help the one shots, as it'll be less easy to do it, but you are also buffing those tanks up as well.
And yeh Circon had a rant about the arty, many of the arties on tier 5 and 6 are not just broken, they are just flat out OP, if you look at their pen, DPM and alpha compared to the HP and armour of the vehicles they face, and then the same at higher tiers, you'll see their alpha, DPM and pen is way way too high.
Like T92 has 60 pen and 1300 damage, even with a pen it'll struggle to one shot even many tier 8 tanks and the pen means aside from complete paper tanks like the Grille, most meds, heavies etc. in the sides/front/hull roofs it won't pen. It then has just 1600 DPM anyway, even if it pens, so realistically it can maybe take like half the HP of a tier 10 tank every minute if its lucky.
Then the M41 HMC, it has 550 alpha on tier 5, so it is able to one shot most tier 5 meds, almost all tier 5 TDs and lights, and high roll on some of the heavies I think, plus it has 38mm pen, which means loads of tanks can be penned, and then it has a 24s reload, so it can pretty much one shot two tier 5 meds every minute and is more likely to do so because of the pen.
It's literally 3-4 times more effective than the tier 10 arty.
It baffles me WG have just ignored it, Grille, M41, M44, Hummel, Su-122A (600 alpha of tier 5 FFS) etc. are just stupid and ruin the mid tier experience, completely easy to play and very dominant. Pretty much all of them make players over perform, especially average or below ones.