Aren't Surly Cross Check and "Ultralight weight" mutually exclusive terms?
You could spend a lot of money upgrading brakes but, how much did you spend on your bike?
Is it worth it? Those TRP brakes run $160 (each) for the low end up to almost $400(each) for the higher end. I would say that Disk brakes are always an option if $'s aren't a concern. You'll get superior wet weather braking as well as good dry weather braking as well.