Pasta can be made from many types of flour. Often, this is predicated on style of pasta or the dish. 100% AP flour will be just fine for your ravioli. I use it often when making fresh pasta.
Substituting the AP flour for the semolina might impact the hydration. I would hold off on the water at first. If the dough feels too dry, add water a tablespoon ...
You may just be cooking too much at once. When I make lasagna or rolled pasta, like cannelloni, I cook 2 to 3 sheets at a time, building my lasagna (or filling the pasta) as I go. I remove the cooked sheets to a clean kitchen towel. Proceed with the construction when they are just cool enough to handle, then add more fresh pasta to the cooking pot.
Another reason: When simmering tomato sauce for a long time, the tomatoes lose some of their sharpness/acidity. This makes for a smoother and sweeter tasting sauce.
This is also addressed in What's the source of the sweetness in tomato sauce that's simmered for at least four hours?
For the record, I just experimented with it.
A little essence of the coconut milk with some Emmental and cream cheese, was not a bad experience. It was interesting, if not a little bit odd - could be improved somehow, but it's not screaming at me to be explored.
Once I also added some of the other ingredients, namely the beef stock and the flavours from ...
maybe they stick because they are overcooked...however, when boiling any type of pasta you should always add a spoonful or so of vegetable oil to help them separate.
I never pre-cook lasagna sheets...fresh pasta cooks so quickly that it will be thoroughly cooked while in the oven, even if every sauce is pre-cooked...and even store-bought dry lasagna sheets ...