Nobody wants to do bounties for enhancement cores. If doing scrapper bounties wasn’t fun why would changing the name to gunsmith bounties make them fun? Instead add them to weekly milestones as end game for after you hit max light. They’d be farmable by doing most activities and makes the milestones worthwhile after hitting max light. Also, as most have stated, consider taking them out of the cost of infusion altogether. I’ve masterworked one set of armor since Forsaken before realizing that that was a foolish waste of cores. Nearly all my masterwoked weapons are from curated rolls because I’m afraid to use them on anything but infusion. Does that sound like fun to you?