Oh God, just do us all a favour and stop commenting on balance.
SM =/= GK. Their ecos are totally different. I would rather have a melta gun on my GK dread by default than an assault cannon, yet I would say the opposite with regards to the SM dread. This is because, put very simply, GK benefit from additional AV sources much more than SM do as GKs AV sources are far less efficient and tend to have both higher sunk costs and/or increased upkeep (in the form of actual upkeep and bleed).
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Because you have to pay extra for that. And no one pays extra for a weapon that will become less relevant in T3."
Right, well that's not true, because like I just said I often get the flamer on the GK dread vs IG and sometimes vs Orks. The claim is also refuted by the very fact that people buy the assault cannon on the SM dreadnought, or the Khorne dread, both of which do great in t2 but come t3 are much less useful due to all the tanks flying across the battlefield. There's such a thing as macro too you know? Maybe I want to upgrade my dread to devastate his infantry because I want to end the game right here, right now in T2 with a huge vehicle push in t2 from a really heavy t1 (which forced him to get lots of infantry that are weak vs my T2 vehicles)?
Everything isn't so clear cut. Most games don't even end up going to T3 (that I play at least and yes, that includes when they're balanced games

).
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GK get a free pass on everything. Every fucking thing. They have all the best units/upgrades. This mod is turning into a fanboy GK fapfest."
Well, statistics clearly show otherwise considering very few high level players deem GK to be viable in any MU or even in team games. I do on the contrary find them viable (when they don't bug out

) in certain MUs, but they're certainly not OP at all, in fact the sheer uselessness of them vs orks or nids makes them rather UP considering they don't have two MUs in which they are as favoured as they are disfavoured in those MUs to make up for such.
Furthermore, your point about them having all the best units/upgrades is rather moot because once again you're not taking into account the ecos of the different races whatsoever. Are IG useless because in a 1v1 scenario their units are absolutely dreadful? No. Is chaos inherently better than anything but GK just because their units achieve near-full potential when alone in a 1v1 scenario? No, only noobs would think so. Is eldar melee completely overpowered because banshees are the "best" melee squad you can buy in t1? No, if their melee is OP it isn't because they are the "best" melee squad you can buy in t1, but rather that they overperform in some way for that given price.