Great original post and some good contributions as I scanned the pages but, will read the thread as time time allows.
I had a mountain bike stolen that my dad bought me from the USA during a trip from my local college when I was young. Absolutely distressing and now as the cost of bikes easily sky rockets losses will be no better.
As a born again cyclist, I am looking for something compact and portable but, as strong as possible (aren't we all), so will have to review the comments and recommendations as carry an Almax 16mm is not easy or practical even on a motorcycle let alone a pedal cycle!
For what its worth, I always cycle around the blocks if traffic/foot fall looks a bit heavy around my house ensuring I don't slow down as I approach it, so it looks like I am just cycling in the neighbourhood and then when its quiet, I dive in.