jyl, The only way to use a close ratio rear and still have low enough gear inches for tough climbs is to run a triple crankset. Compact double cranksets have aesthetic appeal and can have a very large span of gear inches, but at the cost of less than desireable wide ratio differences in the most used gears.

When I hurt my knee I rebuilt one of my bikes with an 8S 52/42/30 coupled with one of three cassettes, 13-23, 13-27 and a 12-21. The 13-27 worked well in the Texas Hill Country while the other two worked well on the coastal flat land when the 30T wasn't touched.

Brad