You most certainly can, because you can use objective, empirical, statistical analysis of games to observe which powers win the most. While I agree that France is the strongest, I believe this to be the case not because of your opinions about France's strategic position, but based on actual results. Someone could just as easily claim Russia is the strongest for a reason that can't really be confirmed or denied in and of itself, like that Russia has 1 more center to start. That seems like a pretty big advantage, but in the scheme of things really isn't. So the reasons why France is strong do not necessarily have to be the reasons you specified. [In fact I think your reasons are very good, but it is objective analysis of results that shows what power is stronger, not armchair arguments].
The REASON one can say that France is objectively better isn't because of some subjective analysis of France's position. The objective reason is the objective results from matches.
And that same basis can be used to evaluate the other powers.
Selecting powers is very much relevant in terms of gameplay balance. If you wish to defend the asymmetries of the game as negated by the playstyles of the players, then there has to be some way for players to ensure they can select the power that suits their playstyle. My argument isn't relevant to the discussion as a whole but it is VERY relevant as a response to your statement about playstyles.
What if 90% of players have a playstyle that is best suited for a traditionally strong power like France? That would EXACERBATE the problem of imbalance, because the games would be even *more* dependent on which player was lucky enough to get France. The fact that seat selection is random is terribly relevant if players, or their playstyles, converge on the same power or several powers as being strong.
In fact, explaining my argument further has caused me to realize that it is in fact a counter-argument to the idea that any power is inherently strong - it could actually be that France being really strong in the statistical results is actually a result of France being suited to the majority of players' playstyls and not really based on an inherent attribute of the country. I'm going to chew on that.
However, even if that is the cause of imbalance, it's still possible to solve with something like the bidding system I've been playing with the last year or so.
I never made an argument based on bad players, so I agree that it's irrelevant, but you're the one who brought it up.
If you mean to talk about my argument that Turkey is strong defensively, which is not premised on players being good or bad, but in having different "play styles", then it is very much relevant. In order to win, a player has to first ensure that he is not *eliminated*. The whole game and all powers' strategies are premised upon that. The longer and harder it is to be eliminated, the more chances for a diplomatic coup, the more chances for forcing a draw, and the more chances for error by opponents that can be turned in a victory or at least a stronger draw. That is an advantage for Turkey that has to be seriously evaluated, and MIGHT be (though I can't prove it to be) the reason for Turkey being so successful.
This whole monopoly argument doesn't respond to what I'm talking about, because I'm not premising any of my arguments on the idea that players are idiots. I'm only discussing high-level play.
However, if I were to analogize to Monopoly myself (a game which....bears little resemblance to diplomacy, but I digress) I would say this: what if Monopoly didn't have players trade for and bid on properties, but the monopolies were distributed at flat-out random? Sure, good players would be able to increase their chances of winning by a lot against bad players by knowing when to build up and when to store chash, but you and I both know that Light Blue has early game advantages that can snowball, and that in the long run the free parking corner is the most profitable. Assuming all players are very good and not apt to make many mistakes, it becomes a GIGANTIC advantage to be dealt the stronger monopolies.
Diplomacy has that problem.