The creation of large prints was the main reason for my move to MF digital, back in 2008.
My opinion, is that the more native resolution the better, as there is no better solution to native dpi at 360 for Epson and 300 for Canon. And it's the same issue if you are having the prints made, either inkjet or dyesub.
I recently finished a huge job where the customer pulled images from as far back as 2005 mostly 30 x 40 but some larger. May of these were taken with the 1ds MKII @ 16MP and stitched (most times 3 images Vertical to create 1 horizontal). They also pulled from many of my Canon 5d MKII shots @ 20MP. My initial thoughts when working on the quote was "no problem I might have to rework some of these Canon shots, but they can get the job done at 30 x 40). I was surprised to see that the best images I had to take to this size were from my P45+ and Mamiya 35mm or 28mm and most of them were not stitched. These files taken to native resolution from C1 and then printed at 360 dpi in LR were amazing in the details. Working on this project I found myself going back to the customer several times to attempt substitutions Phase for Canon/Nikon as the Phase files were just going to make a larger print easier. As for interpolation engines, I have tried them all, (currently I still use LR) but none equal a large MP capture at native resolution.
So back to your question, Yes, I feel you will see a difference in the 50MP capture resolution over the 24MP of your Lecia. I have never used the Lecia but I have used plenty of 21MP, 24MP and 36MP CMOS 35mm cameras. In the job, I was surprised also to find that some of my best Nikon work from the D800 and D810 @ 36MP resolution still did not rival the work from the P45+ in output resolution. I can't answer why, as I used the same raw converters on all the files. The Nikon did much better than my older Canon 5d MKII @ 21MP but the 39MP and 60MP from the Phase backs still had more useable details when taken to 360dpi.
One other note, my technique is to output to 300 dpi from the raw converter and then print the final image at 360dpi from LR allowing LR to make the final 60dpi uprez. This works best to me, but is just one way of hundreds to get to a 30 x 40 and I just wanted to pass on my findings.
I am printing on a Epson 9900. This particular job involved both canvas and paper. The largest print was a 36 x 96, (largest single print I have ever made and stretched) and it was from (2) P45+ horizontal images stitched and looked very good in the final print.
Paul