I made a small change in my workflow and it seems to work like magic. First I moved all "note:" comments I had written in the source code (to find them "later") into a list of issues, so now the two most important lists are issues and bugs. Then I began to put a date in a fixed item to keep track of development pace. An actual example of a fixed bug from Teemu's bug list:
127. Sidestats drawing is not dynamic, has static locations (changed to offsets) [21.9.2019]
For some reason, doing it this way, is making me really focus on a single problem like a bug or issue. And when these issues were comments in the source code it was difficult to figure out what to do next. I guess in a list they make a bit more sense, because you can pick them in some kind of order. I try to fix major issues and bugs first, then less important. Also, keeping track of development pace by date on a fix gives a sense of progress, however small. If you can fix at least one thing per day it's still going to lead into something eventually. It seems like my pace is about 5 items per day which is quite nice, because there aren't really that many of them. Of course, the number of bugs and issues is growing when you test the game, but that's to be expected.