There is nothing wrong with your desire to play multiple DVDs. Yes, as some have suggested, DVD changers may be perfect solution for you.
We service aging audio/video gear and see lots of CD/DVD players in the shop. Keep in mind that these devices have a finite life span. The laser ages and gets weaker, and the "sled" develops some play in it. This combination makes it more difficult for read those tiny little pits on the physical media.
Its kinda like trying to hit the little target in the urinal with a weaker stream that you can't hold as steady as you used to.
Good luck with your retirement. My average work week was 75 hours. I get the leasure time thing. Enjoy.