Excellent to send the letter.
Round here all the city busses I have encounted are very courteous, the give a very wide berth when passing and have on occasion choose not to pass if even if there was room as they know they will be stopping in 1/4mi. They also pick up and transport cyclists as there are racks for bikes on the bus, maybe this is why they are bike friendly or aware.
The school busses on the other hand are terrible and I have had several indidents of them overtaking and merging suddenly into me, of pulling out of schools in front of me, of u-turning in front of me. I guess these are the drivers that don't meet city bus dirver criteria
Al