Personally I think the camera body regardless of sensor size make up very little of the overall weight considering the size of some lenses these days. Personally I use mainly f/2.0 rather then F 1.4 lenses for both saving in weight as well as the saving in cost. Additionally I'll limit the number of lens I take on a trip to say two or three; example I'm head to NYC this Sat for a 3 day weekend I'm bring my M9, Summicron 28mm and 50mm Summilux, I'm than going to some Island along the Georgia coast for a week in April for which I'll also bring my Voigtlander 21 f/1.8
As far as a laptop goes I'd rather just bring a small tablet like my IPAD or just a cellphone and wait to process images when I get home.
Trying to see something new whither I'm visiting someplace new or a place that I've visited many a time before.