Good default values for disk monitoring

[Teresa e Junior]

Hello! I'm in the process of discovering Monit, and I am happy with the 
results so far!

I've set up a couple of rules already, but disk I/O is something I find 
very difficult to understand. Based on the examples I found in the wiki, 
I have the following rules:

check filesystem root with path /
  if read  rate > 1 MB/s for 30 cycles then alert
  if write rate > 1 MB/s for 30 cycles then alert
  if service time > 10 milliseconds for 3 times within 5 cycles then alert

I would like to know, please, what could be a recommended default value! 
For instance, I have a personal server in a VMware VPS, with an Intel 
Xeon E5-2650L v4 CPU, 1 GB RAM, and 20 GB of allocated storage on SSD.

Thank you for your attention!