Well, if my 2017 model gets broken, I'd upgrade to the OLED model (and sell one of the docks).
I also thought about getting a second Switch, if the battery of my 2017 model gets worse. The old device would stay in the dock all the time (so the bad battery wouldn't be a problem), would have internet access 24/7 (so setting it non-primary wouldn't be a problem).
The OLED version would be set to primary (for offline access of my digital games) and would be my Switch handheld with a lot of mobile advantages compared to the degraded old model:
- bigger screen (useful for tiny text in games... the eyes don't get better while getting older)
- higher brightness (useful outside in daylight)
- better battery life (useful on the go without a power outlet nearby)
Auto-syncing savedata between two Switches should finally work: