Another big foot here. 49s.
I used Keo’s and SLs for years. I will say you will definitely feel “more connected” in these than in SPD. After years, I developed knee pain and switched to Speedplay and they are more forgiving with tons of float, but produce more hotspots on long rides and some people say they feel like walking on ice (slippery). The “newer” Aero/Walkable Speedplay cleats are also great. I recently made the switch to all SPD because 90% of my rides are indoors, mtb, or gravel and that lets me reduce my shoe count and makes travel easier, especially when you have flipper feet that fill an entire small suitcase.
I do notice the difference on road rides and on the trainer because I had more float on the speedplay. I haven’t done any 100 mile rides since, so can’t comment on hotspots.