France is considered one of the "better" countries to play in Diplomacy. That's true insofar as it a "corner" and not a "center" country like Germany, Austria-Hungary, and Italy.
In descending order, my favorite strategies are 1) Go for the Mediterranean, 2) Ally with England vs. Germany 3) Ally with Germany Vs. England. But I've found France a tough, frustrating country to play when one can't use a Mediterranean strategy (because of what's going on elsewhere). A couple examples:
In one game, England "allied" with me against Germany, than stabbed me, leading to a Franco-German alliance (my least favorite). Meanwhile, Italy stabbed Austria, A Venice-Trieste, and got two builds in 1901, three in 1902, and had her choice of allies: with Russia vs. Turkey and Germany, with England vs. France.
In another game, I had to ward off an Anglo-German invasion. But the English army that went to Belgium marched into the Ruhr, again leading to a Franco-German alliance. But by the time we reshuffled the alliance, Austria-Hungary had stabbed Italy, overextended in a Lepanto opening, captured Venice and Rome, and dominated the Med. With Turkey, Italy, and the Balkans, Austria and Russia had the 18 centers to declare themselves co-winners.
Have I been misplaying France? Or has my inability to control the Med been due to my northern troubles, and the Austro-Italian imbalances? Can I hope for a more "fortunate" result playing France in future games, against, say, random opponents?