I've been waffling back and forth on my answer for a bit now. Poland's 'weakness' (if you can call it that) is that it's totally vanilla until the Classical era, and still probably lagging a bit behind mid-Medieval. He's got nothing to help against an early attack... but most civs don't have anything special in this era either. He doesn't have any real weaknesses other than maybe a habit of beelining to trigger extra policies early and neglecting military tech more than most.
I can absolutely see where the people arguing OP are coming from: a Civ you have to deal with early or not at all smells a little strong to me, but there's plenty of other Civs I'd not leave unmolested either. Greece, Korea, Babylon, and a couple others feature highly on the "kill it before it gets too strong!" list, and those three all have some things to help them be strong in the early game.
I actually think that the fact that Poland is not the best civ for Domination is a statement on how broken are ranged units (the only reason why Arabia, Mongolia, China and England are superior) and how poorly made is the Honor tree. If Honor was any good (and it should be) and if Camels weren't so ridiculously broken in a war, Poland would be the best at Domination as well, by mixing Liberty and Honor.
Strongly disagree; even if Honor had nicer bonuses it still wouldn't make up for murder machines like the Keshik + Khan combo, or a quick zerging by Battering Rams & Horse Archers, or just a wave of Impi.
Denkt, you keep saying Poland doesn't allow for specialization when I've repeated how having multiple policy trees, more than another civ, allows for synergistic specialization and compounded/faster bonuses. Experienced people have also backed up that claim that Poland is indeed either comparable or flat out better than other civs in all these VCs besides military. On top of that, it is inarguable that Poland is the most flexible, and you can change your VC of choice easily depending on the situation. You can repeat your conclusions louder and more frequently, but very few people who know the mechanics of the game well are behind you on this, and for good reason. You'll have an easier time arguing that Denmark is not the absolute worst than that Poland is not the absolute best.
There are good civs and bad civs. Poland is the best or one of the best for all peaceful VCs. Ask around. Oh wait, we have.
Playing Devil's Advocate here: the synergies towards some VCs (Science in particular) aren't really all that strong. For example, Scholasticism is pretty pathetic when you realize how little science City-States actually generate for themselves. I just wrapped up a game where I had EVERY city-state on the board allied to me at the end of the game, and it barely made up 10% of my total science output. By the time Scholasticism was doing anything noteworthy, I'd already won. Per ally you're getting 25% of the output of a mid-sized, AI-controlled and underdeveloped city.
Same as the +Science boosts in Commerce: that tops out at +8 Science per city, that only with a Market, Mint, Bank, and Stock Exchange, plus a Research Lab, and University with Rationalism. Even adding a Factory with Order and your National College, that's a whopping +11 Science... by the time you've reached Electricity.
Does it help? Sure, in terms of general empire improvement - but it's probably not to the same strength as extra scientists like Babylon (plus that early Academy), nor is it the extra Science boosts like Korea + Korea's extra science Specialists and Improvements. Now, if you'd like to file Korea and Babylon in the OP column too...
For Culture or Diplomacy it's quite valid though: e.g. Exploration being added to the essential Aesthetics for Culture, or Commerce added to the somewhat important Patronage in Diplomatic.
well i just squashed Casimir in my latest game. Im using China in immortal quick pangea settings. The key to defeat Casimir is to DOW him at renaissance before he could get his UU the winged hussar. keep the pressure always. he is really tough. I just captured his two cities including his capital and i settle for peace treaty in exchange for another city. after 12 turns he declared war to me again. i was caught off guard. so i bribed washington to DOW to him. That was enough to keep him busy until i squashed casimir.
Frankly, I think it has more to do with killing him before too many extra policies kick in, not the Winged Hussar. The WH is a neat toy but you don't really have to be that afraid of it: it's only a Lancer, after all.