Options for a super-compact crankset for touring (replacing Shimano 105 crankset)
I assume your current crankset has a 110mm BCD? You could go down to 46/33 teeth. (example 33 teeth chainring: https://www.bike-components.de/en/TA/X110-Chainring-4-arm-Inner-110-mm-BCD-p46803/)
The Shimano RX600 crankset puts the rings and pedals slightly more outwards. It might work with a normal road front derailleur, otherwise (officially) you need a GRX front derailleur.
I’d rather go for a traditional width, something like the FSA Supercompact with 46/30t.