just go for traditional khaki... can't go wrong, its the signature billingham look. anything else is a compromise
regardless of your choice, im sure it will be a handy bag.
i highly recommend that you bring all your gear down to test the fit. everyone's requirement is different, and i'm very pleased with my choice.
that said, i'm awaiting the new 07 series to get a slightly bigger bag for a comfortable fit for slightly more gear. i mean, the usual travel camera bag does not only contain camera gear like body/lens but sometimes a thin cardigan (especially in cooler countries) and especially a water bottle.
for a basic outing, i find the L2 more than sufficient for a basic 2 lens set-up as mentioned previously. this past saturday i took my Hk friends around the singapore river and i used it with 16-35L and 50L together with a flash. i further tested the waterproof ability of the bag when it suddenly poured in the evening, very heavily i might add. my gear stayed dry.
i already encountered rain in japan and hk with this bag, so i had no qualms about enduring wet weather.
i can't attest the same water durability to a domke, i might add, although i still use the J3 from time to time.