If your film not good, not matter how you adjust, the contrast is still not there .... at least it does not look natural.
If Bubble trace do not affect your print, ever wonder how I noticed you have bubble trace????

..... Look for the "white" spot .... or the "black" spot ... those should be where the bubble trace lies ......It may not be evidence on your buildings' picture, because of the lost of focus point, but it can be quite evidenatial on your 6/15, 7/15, 8/15, 11/15, picture..... due to close up (???) and syco view, focus point .....
No matter, today me go take Black and White after my exam, maybe tomorrow or Saturday develop it

..... think should have less bubble trace .....