there would probably be a Spanish Civil War anyway. Spain was falling apart.
No. Spain began to (seriously) fall apart after the 98 disaster, wich started a whole chain of reactions (the Crown and goverment weakened, which led to the Primo de Rivera dictatorship, wich destroyed the reputation of the crown and led to the Republic, wich fell apart astonishingly fast and led to the war). Spain had problems, but they were no worse than those on, say, Portugal or Italy. (the lack of war, of course, does not prevent a fascist uprising)
There is a possibility of a Japanese war with Spain instead of Russia for control of the Phillipines. As for the Carribean, I can't really see them coming under US influence without the Spanish American War.
The Caribbean, a few dozen kilometers form the US coasts, not coming under US influence? The Kingdom of Hawaii was two thousand miles away, and look what happened.
The Phillipines (and Puerto Rico -Cuba was a goner due to the revolution) would probably remain Spanish until the great independence movements post WWII than dismantled the European Empires. But Japan would conquer then anyway, and porbably more easily than the US phillipines... unless, of course, the AH cliché of a Fascist Spain comes tru on TTL. A German-Japanese-Italian-Spanish axis and lakced a Spanish Civil War would not only give the UK serious trouble in Gibraltar (and the Axis serious trouble once they had to defend the Spanish coast from invasion) but it would mena thna Japan had not need tp irritate the US invading the Philippines, held in allied hands.