I think the main point is security-level. but as far as I am aware you do need routes configured.. be it static or dynamic for two subnets to talk to each other. 

I might be wrong but doesn't by default interfaces of the ASA kill the ping traffic, if the network is setup correctly you might be able to ping PC2 or Switch2 but not ASA2 inside interface from PC1.  

Best would be to connect to the Aironet via console cable and setup the IP address yourself.there that should help you.http://www.cisco.com/c/en/us/td/docs/wireless/access_point/2700/quick/guide/ap2700getstart.html