i mean, its not like you do them one at a time, you do them a handfull at a time, and while doing something else, too, like srikes or gambit or crucible, as opposed to progressing a single bounty and only that bounty.
additionally, all of those bounty completions will grant additional XP as well, progressing your season pass completion even further! which in turn grants you even MORE dust!
its literally the solution to all of your issues.
EDIT: sorry, i thought you were OP.
its literally the solution to all of OPs issues.