Hi Jeffrey!
Thank you for bringing your question to the Disney Parks Moms Panel. I'm glad to let you know that Mickey finally put his stamp of approval on the
2018 Magic Your Way Packages and they are now available to book online!
As far as stroller parking goes, there is stroller parking near the entrance to every queue and a friendly Cast Member should be able to point it out to if you if it's not immediately apparent. For some areas you can leave it in one location and hit multiple attractions at once, like
Peter Pan's Flight,
"it's a small world" and
Mickey's PhilharMagic. For others I would probably move it with you between attractions. While there is usually a Cast Member nearby keeping on eye on the strollers and helping Guests maneuver their's in and out, they aren't able to keep up with who each stroller belongs to. For this reason, I wouldn't leave any valuables on your stroller, just to be on the safe side! I have left a diaper bag or toys with no issue, but I usually keep a small wristlet with my wallet and cell phone in it, just for precaution.
Please let us know if you have any other questions and we hope you have a magical trip next June!
-Lindsey ºOº