For the ebb and flow of the Federation-Cardassian War, I looked to Earth history for inspiration, specifically the Pacific theater during World War Two.
The Japanese spent years conquering China and French Indochina, and carefully planned simultaneous attacks on Pearl Harbor, Wake Island, the Dutch East Indies, Guam, and the Philippines. Over the next three and a half years, there were major battles at Midway Island, Java Sea, Coral Sea, Philippines Sea, Iwo Jima, and Okinawa, to name a few, and dozens of smaller battles and protracted campaigns to retake the South Pacific Islands.
The Cardassian War differs in two important ways. First, the Cardassians didn't plan to invade the Federation. Rather, they thought they'd take "just one more planet, they didn't mind the last three times". Obviously, they miscalculated (as did the Japanese when they attacked Pearl Harbor). However, unlike the Americans, the Federation sought only to hold the line and not to push into Cardassian territory. Historians in the 25th century would conclude that if the Federation Senate had the political will to allow it, Star Fleet could have easily smashed the Cardassian fleet and invaded Cardassia Prime.
The source material, as posted on Memory Alpha, said the war ran from 2347 to 2367, when the Armistice was signed. There was a line-item that said the war tempo dropped to occasional skirmishes after 2360. Still, I felt 12 or 13 years of constant war seemed excessive for the timeline. If it had drug on that long, the Federation would grow weary of it and unleash the full weight of Star Fleet. Ergo, I built in a "pause" after about four years, with the failed coup in 2352. I figure that the limited resources would cause unrest at home and hinder the war effort. That gave them a few years to rebuild and try again in Round Two, years 2358-2360.
So, that's my view on how the war might have played out. If you disagree, feel free to suggest alternatives.
If there is any Official Canon that conflicts with *anything* posted above, please post a correction as needed with a citation.
Again, this was developed to allow fan-fiction to "live in the same universe", so please do list the title of your stories and the dates in which they're set.