One of the fascinating curiosities you're missing out on is Pressure Stall Information (https://docs.kernel.org/accounting/psi.html). Here's what the PSI gauges look like in htop when kernel support is available:

  PSI some CPU:     0.37%  0.78%  1.50% 
  PSI some IO:      0.38%  0.33%  0.25% 
  PSI full IO:      0.38%  0.31%  0.23% 
  PSI some memory:  0.02%  0.04%  0.00% 
  PSI full memory:  0.02%  0.04%  0.00%