As an owner of a 42 LRC and previous owner of a 43DC I can address some of the pros and cons.
The LRC is much easier to get around on for us older folks, the pilot house doors on both side make life easy.
The engine room is better due to the smaller engines.
The ease of getting on and off the boat at different elevation docks is much easier with the LRC than the 43.
Having run the TN, Cumberland, Ohio rivers as well as the Tenn-Tom to the St Pete area for the winter you just have to plan for the currents more with the LRC than the 43.
Being able to plan fuel purchases when you find good deals is also a great feature.
Having said all that I really liked the 43 as it was a great handling boat. Either boat would do well for the loop. I wanted the LRC as when I retired 4 years ago we became full time cruisers and the LRC is more comfortable for us and much easier to maintain.
Climbing those flybridge ladders aren’t as much fun anymore..