The problem, I think, is that every single power is substantially impacted by the metagame, maybe even more so in gunboat compared to press because of how it's impossible to communicate and therefore unspoken "norms" can dominate so much.
Austria is a poor gunboat power in almost any world just because he has so many threats from essentially every direction, and even if he lives for a while he can get knocked out in relatively short order by any of his three main neighbors. Without a couple of fleets he'll always be under threat from Italy (or whoever conquers italy I guess) but with fleets he won't be able to fight very well on land which is his bigger concern.
Russia is a poor gunboat power in almost any world just because he is potential enemies with virtually every power on the board, and so much of Russia's standard diplomacy power comes from the ability to impact things around the board and coordinate. If Russia can't message Italy and/or France to get help from them, or message Germany to negotiate over Sweden/Scandinavia, etc etc etc, it becomes really hard. A meta where Germany usually lets Russia into Sweden would help, but even there it's just so easy for Russia to collapse under assault from multiple theaters.
Overall I'd tend to say in terms of power rank...
1) France
A meta where everyone piles on France early (INCLUDING Italy) would be hard on France, but even there, you can potentially fight back for a bit and see whether everyone else's positions collapse. France is probably the power most equipped to handle aggressive (but uncoordinated) behavior by neighbors early on and not collapse. France is helped by a meta where Italy doesn't normally head west, but even ignoring that bit, is a very strong power. Which makes it even funnier that I almost always shit the bed as France but lolsmith
2) Turkey
Turkey is hurt by the site meta of A/I alliance play, but even so is a fairly decent power, or at least difficult to kill off. Austria can collapse at any time, Russia has lots of problems, and France is a potential western juggernaut that can put Italy on a timer to get rid of Turkey before big bad blue comes after him. Turkey is also probably the #1 power in a more beginner type board where Italy doesn't work closely with Austria, Austria makes paranoid moves against Italy, etc.
https://www.playdiplomacy.com/game_play ... _id=137234
was overall almost stupidly easy to solo as Turkey when Austria screwed around in 1901, Russia was friendly for long enough (plus he stabbed badly and predictably in 1902 giving me great "cause" to crush him at the same time England was rolling him up north), and the west never really resolved itself
3) Germany
Germany has a weak neighbor to the east (Russia), one to the south (Austria), and its northern/western neighbors (E/F) are kind of hardwired to fight each other most of the time. Probably the biggest issue Germany has is that England can potentially dominate it through sea, and if it builds fleet power, then France can potentially dominate it through land. Basically, whichever of E/F conquers the other is a massive pain for Germany to conquer or even hold off. That said, the E/F war is reasonably likely to create some opportunities for Germany to strike at a key moment against one and then the other. It's a hard power to master, but just like Italy, no one really is coming after Germany right off the bat, which does give it some flexibility to read the board and choose good allies.
4) Italy
Lots and lots of options to play, no real fundamental enemies early, etc. This ranks lower in the hands of a poor player, and lower when Austria goes anti-Italy early instead of fighting for Greece. In the hands of a strong player, and/or on a site meta where A/I is normal early, this underrates Italy.
5) England
Not nearly as hard to kill as Turkey, but also not fundamentally hampered by the obvious potential for two of its neighbors to ally for the sake of necessity. England's fate is heavily influenced by the opening turn, in particular the hostility level (or lack thereof) from France and Russia. A French navy in ENG and a Russian army in STP leads to a pretty short game for England, but favorable openings by neighboring powers can lead to good opportunities. If England can ever break into MAO early in the game, he'll have a really strong tactical position... but getting there is usually pretty hard to pull off.
6) Austria
A meta where Italy attacks Austria early makes Austria #7, but Italy has a fairly hard-wired incentive not to do that since it just hands power to R/T (mainly T).
7) Russia
If Turkey is doing well, he'll eventually crush Russia. If Turkey is doing bad, then one of A/I will eventually crush Russia. If England or Germany is doing well, then they'll eventually build fleets and roll up Scandinavia. Other than that, gunboating as Russia is easy

This bumps to #6 and maybe even #5 in a meta where Austria always gets crushed early, since that creates opportunities for Russian growth, and picking a winner between the I/T fight can help as well... but it's still pretty rough overall. Probably the hardest power to play on a high level board, and there are a lot of landmines on a lower level board too.