my "beater" singlespeed commuter is a surly...

nice enough to ride nice, not so nice as to attract ridiculous attention.

it gets locked up in center city philadelphia (not the nicest most looked after location). one bike has already been swiped from me here, but now i use two locks a NY chain and a u-lock.

more than one lock (preferably a chain AND a u-lock) should protect your semi-bling investment well enough that you shouldn't have to worry about theft. if the locks are too heavy leave them attached to the rack, thats what i do, they'll always be there when you need them.

as for the riding being potentially unsafe; just try your route... i think you'll know if it's unsafe. if it is, find a safer route...

a weekend of exploration by bike between home and work should open your eyes to any number of safer commute route options.