the idea has its origin in a post on the IJN forum asking info about an all IJN fleet.
this caused an uproar from some players, predicting that such a fleet would be totally crushed in a fleet battle,
for "obvious reasons" (still to be developped, but quite understandable).
this warning was certainly  right, in the case a single nation fleet would face an all nations fleet.

from there, my suggestion:

1) allow the creation of single nation fleets, at players will, in line with the current rules for fleets.
some nations may not be represented, some others could have severaldifferent fleets.
2) set rules and procedures, mainly the ship class limits, maps, duration and so on for a league that only
single nation fleets could enter.
may be the existing FL rules would require only minor adjustments.
3) organise battles between these  fleets, no matter their nation.
i.e. an IJN fleet could fight an another IJN fleet
4) if the numbers allow it, organise a fleet league tournament between nations, with selections if there
are several fleets in each represented nation.

pros
1) a new mode could spark new interest and offer new perspectives
2) currently fleetless players might be attracted by this opportunity
3) focus on respective strengths and weaknesses of each nation, giving a sharper, more contrasted picture.
4) open the way for a new class of  nation specialists and experts
5) potentially allow the development of new strategies and gameplay.
6)..

.cons
1) new mode= new organisation, more hassle for the mods
2) too specialised, therefore too few adepts= battles would be meaningless
3) too much "nation linked", would unneccessarily ignite "nationalist" wars
4) if the nations, as they are, proved to be blatantly un-balanced = endless requests for a new balance
5) (and many more) = just unappropriate, unwanted, irrealistic or whatever...

interested?
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