It's main drawback for today's me is the low 'resolution' of the screen in modern-day-terms. These days a 1920x1080 is almost mandatory as a minimum.
Therefore I have switched off my modern gear and intend to use an old X200 with a minimal Debian/GNU installation to see how far I'll get.
Any thoughts or tips for making this old computer live up to its legacy?
Trick it out with as much RAM as you can.
upgrade to an SSD.