We are rope droppers who travel in summer. Our most recent trip was last August 5 - 12 with crowd levels at a 9. I usually make my first for 9:30-10:30 mark, but don't go until the end of the time window. Then i make my second for as close to 10:30 as possible, so I can go from one right to the other. I make sure the rides are fairly close together (we did peter pan/mine train one day and splash/big thunder the next). Then I make my third for after lunch, somewhere between 1 and 3pm (MK day 1 was splash, MK day 2 was mine train). Then we get a 4th from a kiosk for later in the evening if we're taking a break, or for a current time if we're sticking around. We've never had trouble getting pretty much whatever we wanted at the time. I know my answer is focused on MK, but that's the only park we used more than 3 FPs each day.
We're going to employ the same strategy for this July. We only had to wait in two lines of any real length (30 minutes)
A note on kiosk lines...
Sometimes they look REALLY long, but in reality, it's just a bunch of families standing all together. So it might look like there are 20 people ahead of you, and it's really only 4 or 5, because the people are all together. The kiosk by the jungle cruise seemed to be the easiest to get to, and the one in the breezeway between frontierland and adventureland was always annoyingly backed up. It wasn't that it took a long time to get through the line, but it's just a smallish space and people who were in line for the kiosk tended to be in the way of everyone who just wanted to shop, use the restroom, or just pass through to get to the other side.