I decided to take up hiking a few months ago. Our first venture out was to Piestwa peak. This park was recommended to us by a ranger that mistakenly thought my 5-year-old daughter couldn't handle a double black diamond. We passed the easy trail that day and ended up at Echo Canyon on Camelback (she made it to the top!).
This weekend, out 3-year-old wanted to go hiking. We decided that we should try Papago's trails, since all the ratings are no more than moderate. My first problem with Papago is the lack of clear trail markings once you get into the trail itself. The area is pretty open and you can see all the extra trails others have made, despite the "keep off for revegetation" signs. The few markers that are there have no trail numbers or directional guidance. We thought we were going the right way to find out we left the trail completely a few times. My other, MAJOR problem with this park and trails are the amount of trash and broken glass strewn about. My three-year-old fell a couple times on our walk. With the glass and other "fun" items to be found, infection is very likely. Every other Phoenix park with hiking trails has a pack in, pack out policy that seems to be followed much more closely than here.
I would imagine that mountain biking would probably be great here, but I would be concerned of flat tires from all the glass. The area is beautiful, if you can look past the basic upkeep being neglected.