Profile of Sander93

You're making an assumption base on a wrong correlation. That's not even subjectivity here. Map popularity have little to do with being considered by people as good map.
Once you understand the game mechanism (at least for 4vs4) and grinding your ranks you'll naturally be electing your commander pool and maps uppon what you believe is the peak mechanism for you and your factions. And on 4vs4 those are artillery and choke points where super heavy shine, which is the definition of Port of Hamburg.

I highly doubt the majority of the playerbase solely plays for ranks. There's huge variety of strategies used in 3v3 and 4v4. There is no single meta like in 1v1 (tourneys). Most people play for fun or at least want some variety, even at high ranks. Most players at all skill/rank levels just seem to prefer easy grinding maps over more tactical maps, which does make these maps good if popularity is used as a measurement. My point remains that what makes a map good is subjective, based on a player's preference. And that with player preference varying wildly, popularity seems to be the only proper quantifiable measurement to define which maps are good and which ones aren't.

I'm an aggressive and tactically creative player so I personally think Port of Hamburg is a terrible map because there are 0 ways to outflank or surprise your opponent, but it is one of the most popular maps because most players apparently like to mostly camp and throw arty at each other, which does ultimately make it a good map for the game's sake.

Anyway we're blowing way off course here.

Non-laney maps. Open maps. Maps with lower number of buildings around key points I guess. Generally the best maps are those that favor flanking and wide open battlefields as opposed to campy/lane-y areas.

What is a good map is rather subjective. For example I'm sure a lot of good players would agree that open maps that allow flanking are better, yet the most popular 3v3 and 4v4 maps are the laney maps like Port of Hamburg and Red Ball Express, even on the highest levels. Even amongst the top 1v1 players the preference for maps varies wildly. There is no universal rule for a good map. All maps will always favour or disfavour certain factions or playstyles, and therefor favour or disfavour certain players, so it mostly comes down to personal preference what is a good map or not. The only way to really measure how good a map is, is simply by looking at how many people do like it as opposed to how many dislike it.

In regards to the latter, the newest 1v1 maps generally seem to be liked a lot so that's good news.

Late-game prefomance of osttruppen is perfect in all game modes.

Osttruppen are really bad in 2v2-4v4 where combat strength of units is more important than the speed at which they can cap the map and overwhelm the enemy. This is why they are meta in 1v1 but aren't seen in higher level teamgames at all.

Besides that I think that the dynamic of Osttruppen (1v1), that they are very good for the early and mid game and then drop off sharply towards the late game, is actually a very interesting strategic dilemma that makes picking Osstruppen a bit of a gamble, and thus a proper strategic choice. If the enemy can't be effectively broken early/mid game, then they will likely win the late game. It is especially interesting for Ostheer because it allows them to a aggressive early game where they are normally a defensive faction until they get tanks, so it turns around their playstyle. I don't think this dynamic should be changed (as in major buffs/changes to their late game performance), except for maybe very small changes to combat power scaling. The game needs more of these interesting dynamics and choices, not fewer.

I don't think the tanks are an issue, I think they are all good within their context. Beyond some small tweaks I wouldn't touch them.

The Cromwell is good for its timing (if you can manage to skip Bolster/AEC/racks then Brit tank teching is very cheap), and with the Comet/Churchill being available stock to transition into it isn't really meant or doesn't need to be a workhorse like some of the other medium tanks. I don't think it needs anything. It's a good unit to keep up the pressure in the mid game to bridge the gap to Hammer/Anvil.

The Firefly is pretty much as good as the other TDs when it can operate in a relatively confined space, so 2v2-4v4 maps, and it becomes great with veterancy and/or a Command Vehicle. I can see how its slow responsiveness (low mobility and stock turret traverse) can be a problem in 1v1 though. Not sure if I'd change anything. 1-2 vet 3 Firefly/flies with an AEC Command Vehicle is easily the best AT in the game, although it's very expensive to set up. Perhaps switching around the vet 1 (+15% acc/dec) and the vet 2 (+35% turret rotation) bonuses might be an option that would help it in 1v1 without having too much impact on the larger modes.

The Centaur is great for its timing too, although a bit of a risk (no AT obviously). Its vet 1 ability is very powerful because it can instantly wipe out ATGs (if it doesn't bug out). One adjustment could be giving it higher mobility and nerfing its moving accuracy, so it would be able to get out of tricky situations more easily without becoming too good at wiping on retreat.

The Comet is a bit too good now, I think a small nerf to its cost or to the WP (like higher aim time) would be fine.

The Churchill could probably lose a population point, but not much else I think. The Comet is simply the better option in most cases because it is more versatile, but the Churchill itself isn't bad at all.

is suppression affected by accuracy? because if it is then MG34 suppression is abysmal at far in contrast to MG42 suppression... 0.35 vs 0.28 is significant...

It doesn't. Base suppression per second is calculated by ROF x suppression per bullet with the suppression threshold being 0.2. There are some factors that may influence this besides cover, but nobody really knows how that works. Presumably those are the same for all HMGs anyway.

and it kinda shows... the MG42 suppresses alot faster than the MG34 at far...

It doesn't. Suppression max far range against neutral cover is 1.16s for the HMG 42 and 1.28s for the HMG 34. Barely a noticeable difference.