Until I discovered that I was paying about 2 dollars a tomato in embedded costs for each one I grew in Texas (where tomatoes are not indigenous), I used fresh tomatoes on pizzas. The problem with using them is that it's hard to get a nice, sweet, low-acid sauce out of them. And you have to use a ton of them if you are using a food mill. I found that using the small grape-type tomatoes worked better than the standard tomatoes, and especially so if I dried them in the oven to get a more sweet and intense flavor out of them. The closest I have found to fresh tomatoes are the San Marzano tomatoes. While they are often considered sweet, they are not particularly so. But they are low-acid. And they are very good on Neapolitan style pizzas, or combined on other types of pizzas with my favorite canned tomatoes, the Escalon 6-in-1s.
If you have a lot of fresh tomatoes, you can use them on pizzas in combination with the other types of tomatoes mentioned. They lend a nice, fresh flavor. Using you food mill does have the advantage of removing skins and seeds, which can sometimes have a bitter quality, but, as you have noted, you will end up with a lot of juice and not much pulp. In that case, you will have to boil off a lot of the liquid and then use herbs and spices to produce a decent sauce that you can then use on pizzas. You may also have to add some tomato paste or tomato sauce to bring up the flavor level and intensity. Or, you can spare yourself all that agony and just buy some Escalon 6-in-1s (or comparable tomatoes from Stanislaus, if you can find a source of them).