Yeah, I think you're right DBasler. Not only that, but at ~ 2000Kcal/day I'll be surprised if I add too much to that pull right now.
One thing I've noticed is that my strength did decline somewhat when I hit 50 or so; however, I attribute this more to age related decline in the efficiency of the nervous system, than any musculo-skeletal issues. I think I'll be doing more monitoring and training with HRV (heart rate variability). I've been using--not as consistently as I need to--a program called Heart Math. It teaches you to voluntarily enter a state they call "coherence", in which input from the sympathetic and parasympathetic branches of the nervous system are balanced, thus preventing "sympathetic overdrive". It really does help with recovery, as well (when using HRV as a diagnostic tool) as letting you see when your nervous system is recovered and ready for hard training, or conversely when it's not.
The "home" versions of HRV training and testing obviously don't have the precision of a lab or medical setting, but they are nevertheless helpful: at least that has been my experience.