Bugs can be filed at https://bugs.96boards.org/ .
Please note that submitting bugs does require you to provide detailed information on how to reproduce the issue otherwise developers are left with little choice to but to close bugs as unreproducible.
At minimum you should provide exact version numbers of the images you installed together with the install method (fastboot, install from SD, etc). If you were forced to make changes to sources.list then a diff would be valuable to make clear what you think may have been omitted.
It is very important to include as much detail as possible; I am currently running the latest debian release (https://builds.96boards.org/releases/dragonboard410c/linaro/debian/16.02/ ) and have not observed problems in any of the areas you mention.