Sweden: Sweden is a russian province.
I've seen many FTF games in which Sweden is the last refuge of the Czar, after Turkey (and occasionally Austria) has overrun his starting four SCs. This mercy position is one fleet, sitting in Stockholm, but being a real nuisance to Germany who's also trying to deal with France, England, and Turkey.
The question over Sweden early in the war, of course, is:
Does the Kaiser bounce the Russian F GoB-Swe with F Den-Swe, or
does he let the Russians have it?
German F Den-Swe, Russian F GoB-Bal makes the Kaiser look like a dupe.
He does get Sweden all right, but he doesn't even get Denmark, and now
both Kiel and Berlin are threatened.
German F Den Holds lets the Russians take Sweden and, if accompanied by
skillful diplomacy, may even earn their aid against England.
Still, two years later may yield a strong, fleet-rich Russia in the north, holding St.Pete's, Sweden, Norway, and maybe at least part of England, awaiting the perfect time to swoop down on Germany's exposed north coast ... remember, Russia can march an army or two through Poland, too ....
As for the Swedes themselves, I believe they would rather be independent. :)
Sweden: The most likely neutral supply center to remain unconquered after 1901 (27.8% of the time).
If Germany moves to Denmark in the Spring, he can threaten to bounce Russia out of Sweden. This will weaken Russia but will probably piss him off too. He might even move into the Baltic Sea and then Germany is in trouble, especially if Russia gets armies into Prussia or Silesia in the Fall.
Germany should probably stay in the West and not provoke Russia until the western triangle has been resolved, unless he knows he has Austrian or Turkish support. It is not in Germany's interests if Austria falls quickly, so he can threaten to bounce Russia out of Sweden if Austria is attacked in the Spring.
Late in the game, Sweden just about always falls under control of whoever wins out among the Scandinavian powers: Russia, Germany or England. It's very unlikely for Sweden, Denmark and Norway to remain under separate ownership for long.