On possible Alliances, lets look at the little guys first, then work into the big boys club.
- Italy, as everyone has pointed out at this point, isn't going to do anything that's going to hurt them. Especially considering how young and fragile they still are at this point. So they're not going to be fighting Britain or France in the Mediterranean, and they're not going to fight a ground war against Germany or France, alone. This does come with the qualifier
alone though - Italy might be persuaded to fight France if Germany is hammering their Northern border, or attack Germany/Austria is France is doing the same vice-versa. Really Italy is going to go whichever way the wing blows. They won't, however, ally easily with the Ottomans, who are 99% going to be in the London-Berlin clique. So perhaps if France is winning versus Germany on the Western Front, and at least matching or containing the Brits in the Med, and Russia is hammering the Ottomans and keeping the majority of their fleet penned up in the Black Sea; than further into the conflict Italy could be swayed to the French side with promises of African colonies and territories taken from them by the Austrians. A big if. Most likely Italy does as it does OTL; plays both sides, then jumps on the winning bandwagon at the last moment when the victor is clear.
- Persia is another 'minor' player that could be persuaded to join France. Persia by this point has both had major incursions and foreign interference by the Ottomans and the British. On the other hand though, Russia also has its hands in the cookie jar. Really this would be a move for France to keep some of the Brits and Ottomans penned up in the Middle East, allowing them more room to maneuver in the Mediterranean and Indochina. And what does Persia get out of it? Well... if France can make the Russian's promise to curtail their involvement in Persia, that alone might be enough.
- Balkan States, are again, as far as a possible French alliance, going to be merely aiding France to get at the Ottomans and the Austro-Hungarians. Allies of convenience, they open a new theatre in the war, and keep Austria and the Ottomans from devoting all of their resources towards Russia (or in Austria's case, France and/or perhaps Italy). The Balkans gain greater independence from the Ottomans and Austrians, but court the possibility of even more Russian influence in their affairs. Bulgaria in particular is going to be very upset with Germany, Britain and the Ottomans, and not-so against Russian influence as the others. Again, it'll probably cost the French a promise of protections in the post-war scene to get these minor players into the game.
- Spain at this point in time has just suffered the Spanish-American War,
El Desastre, in which Spain lost its two most important colonies to the Americans. It'd be very easy to see
revanchism take off here.
Generación de 1898 leads to the major anarchist, communist, fascist, and other movements that eventually lead to the Spanish Civil War. OTL, in 1909 a revolt in Catalonia was bloodily suppressed. So, long-story short, Spain's not really in any sort of position to take sides during a hypothetical Great War ITL. If, however, they did swing in any direction, its going to be with whoever is against the Americans, and/or whomever is going to put them into a place to reacquire/acquire old/new colonies. It would take quite a lot of French support to get Spain up on its feet again and onto their side. Which really wouldn't be in France's interest, because Spain would be gunning for the elephant in the room..
- America is psedu-isolationist at this point. They've stretched their muscles a bit, and have gained a colonial empire in all-but name in the Caribbean and Pacific. However, on the face of things America continues to assert its non-imperial ambitions, and its lack of an empire. Both of these facts lead America to clash with Britain over several minor points. Historically America has never had a good relationship with the British, from the Revolution to the Civil War to general border disputes ongoing throughout the 19th century. In fact America and Britain becoming so close on the eve of WWI would be ASB if it wasn't historical. Historically, the Americans were against the British, and allied (or friendly belligerents) with the French. France is also the only republican government in Europe at this time, which highly endears itself to the American public and government. Reciprocating, many French people held the United States in high esteem, as a land of opportunity and as a source of modern ideas. The ties between the two were never overly formal, but ran deep; In 1906, when the German Empire challenged French influence in Morocco Theodore Roosevelt sided with the French. However, its going to take a lot for France to be able to pull America into a formal (or even secret) alliance. Regardless of the realities, the perception of the time is that the British Empire is the best of the best, and America is not interested in challenging them either on land in Canada or at sea against the Royal Navy at this time. America stays out of the war, but might be convinced to sell supplies to the French. If so, then the big question becomes does America become more upset about France attacking and stopping American trade with Britain/Germany, or about Britain attacking & stopping American trade and supplies to France?
- Japan isn't exactly in a position to challenge Britain at this point in time, and won't be for several decades. So they're not going to want to go against the Brits; at best they wage an indecisive naval campaign, and at worst they lose Formosa. On the other hand though, the German colonies in the Pacific are very far away from the Fatherland and very close to Japan. IOTL the German colonies were the first European territories to be seized by the Japs, when they jumped on the bandwagon against the Central Powers in 1914. Japan really is just looking to expand its colonial empire one way or another, and Germany's are the easiest to take. So their up in the air. Japan doesn't want to piss off Britain, but they want what Germany has - so any sort of Angle-German Alliance or against their wishes. It'd take a lot for France to swing the Japs to their side, but even if the situation can be changed so that once war breaks out, Japan stays neutral (or, Japan attacks German Pacific holdings but doesn't get into a shooting war with Britain, and ignores French Indochina) that's going to be a win for France.
- Wildcards: various OTL neutral powers.
So in summary, the Franco-Russian alliance is pretty much screwed

They might be able to drag some players into any war involving Berlin-London-Istanbul vs Paris-Moscow that have major and minor grievances against either of those three great powers, and not so much against either France or Russia. But a lot of that is going to depend on Franco-Russian successes in the early months and year of the war, and/or some very amazing diplomatic feats on the part of the French.
So ultimately we'll see an alliance system somewhat like this when it comes to major powers;
Central Powers
-British Empire
--British Imperial Dominions & Protectorates
-German Empire
--German Colonies
-Austro-Hungarian Empire
-Ottoman Empire
Entente
-French Republic
--French Colonial Empire
-Russian Empire
??
-Italy
-Japan
-America
In regards to a 'spark' for the war, I could imagine a greater Fashoda incident or similar colonial dispute being the imperitus for a Grand European War; however for the most part France and Britain stayed out of each other's spheres of influence in colonial matters, so that's a no-go. And with Britain in the German camp, France may not feel strong enough to demand Alsace-Lorraine returned. So we may very well yet still a Balkan Affair, or something involving Russia getting involved in Anatolia.
And that's my two cents and a bit.