I don't have a chart, but my favorite diesel engines for a bus (or truck) are in this order and pre-emissions years (2003 and older)......
International T444E (Same as Ford 7.3L Powerstroke)
I like the International DT466 for it's reliability and especially it's power. These engines can also be rebuilt in-frame.
The Cummins 8.3L is an awesome engine and a powerhouse. Pretty reliable and usually found on large busses.
The T444E and 7.3L Powerstroke engines are very reliable, parts are abundant, and great engines, but seem under-powered in full size vehicles since they range from 190-210 HP
Cummins 5.9L is an awesome little engine and pretty reliable, but like the T444E, they don't have a whole lot of HP, but still get the job done. Parts are also readily available.
DT360 is an in-line 6 cylinder and another reliable engine, but also is no power house.
I do not like CAT engines. Some of them like the 3116 are pretty decent, but parts are expensive and trying to find a Cat mechanic or someone familiar with them is not like finding a Cummins or Powerstroke mechanic.
My opinion on the popular diesel bus engines. Others may have different opinions.