I've always considered Pulp Alley to be the tabletop rule-set equivalent of the old Unimat hobby power tools -- a little workstation you can configure to do just about any job you need to do to make something from scratch. So, I offer you nothing but encouragement in innovating stuff and trying it out...I've been doing the same thing since I started. If you like more detailed perils, go for them -- yours are very imaginative.
With regard to moving perils, I'm reminded that in the Vice Alley supplement, which introduced Bystanders and wandering, there were three types of wandering movement defined: Random (moves in random direction, Cautious (moves away from closest character), and Stalking (moves towards closest character). There was also an Aggressive trait, which expanded an individual peril to a 3" diameter one. If you don't have Vice Alley, I strongly recommend it -- there is a treasure trove of stuff in it, including a non-violent combat system (for social affairs, nightclubs, and so on), and a complete locations system that will allow leagues to control news-stands, hotels, gyms, docks, bars, etc. for profit during the pregame resource phase. This is great material you can add to your own campaigns.
Thanks for posting...very interesting stuff.