I would love to see one of "the big three" develop a good GC meter by using a bandswitch instead of slugs, or freq-specific couplers (have the slugs/couplers built-in and selected from the band switch).
Just use an H series slug. They cover 2-30 MHz, but work fine on 160m, and are available in power levels from 25w to 10,000w. No need to switch anything.