I used that layout in conjunction with info from this page from Beavis Audio:
http://www.beavisaudio.com/projects/Looper-Switcher/index.htmAnd this layout also originally from Beavis Audio:
http://media.tumblr.com/tumblr_lfwjj510Ya1qemwmy.gifOne of the options on the page uses a DPDT switch for switching without an LED.
I've built and used a few of these, and am struggling to work out the "how and why?" of your requirements.
First, you say you don't want to use Send/Return jacks, but they are exactly how you incorporate your whole pedal board into the loop.
Second , you want the looper and chorus in the same box, but with the chorus in the loop. this will mean the chorus will only work when when the loop is engaged, unless you also include an order switcher (also on the Beavis Audio page).
Therefore I believe you would be better off having the looper and the chorus in seperate enclosures.
Finally feedback loopers, get insanely loud, very quickly, and can and will destroy your speakers unless you are VERY careful using them. A non-latching footswitch is a REALLY good idea to stop things running out of control.