All the news and plans for Shadowkeep and beyond is well and good, and Season of Opulence is pretty neat, but enhancement cores are still a problem.
[b][i][u]Infusion is not a meaningful choice[/u][/i][/b]
The root of the problem is the idea that Infusion should be a meaningful choice. Like leveling up, Infusion is a vertical progression that acts as a gateway to higher-difficulty content. Vertical progression isn't meaningful because it's simply a difficulty pass. Choosing which gear to infuse is a formality, as the end goal is to bring all your gear to the level you intend to play. No play-style choice is made here.
Horizontal progression is where choices become meaningful. What class do you play? What subclass? Weapons? Mods? Masterworks? These choices can be made at just about any level, and don't impact what difficulty you're allowed to play at. Instead they give you meaningful choices about your play-style, synergy and efficiency at that level. Even across multiplayer, horizontal progression matters and is meaningful when you combine up to six guardians to make an efficient team.
[b][i][u]Infusion inhibits Masterworking[/u][/i][/b]
Because Infusion requires such a constant flow of enhancement cores, most players don't have enough to partake in the Masterwork system without dramatically slowing their power climb. Hardcore players who sink thousands of hours and make YouTube content might have fully masterworked gear, but the majority of players don't.
The attempt to make progression more meaningful has actually made it less meaningful. One kind of horizontal progression is essentially ignored because the benefits of Infusion outweigh the benefits of Masterworking.
[b][i][u]Flooding cores will make Masterworking less meaningful[/u][/i][/b]
The alternative to removing cores from Infusion is to add more sources of enhancement cores. This seems to be the route taken so far, but it's also not a solution. If enhancement cores are so abundant that Infusion is no longer an issue, then they will also be so abundant that all gear can be masterworked without having to make choices. If the core income is any less, then we're back to square one.
I don't think there is a golden ratio of core income, and if there is, I still think it would be more meaningful in all ways to remove cores from Infusion instead.
You can get three cores a day from the gunsmith bounties and two a day from Spider. Those bounties take longer flying to the tower and your destination than actually completing them. Plus you can do the bounties on two other characters for a total of 11 cores a day. There's also spider bounties if you feel you need more.
You can literally infuse all your worn gear in two days for maybe an hour of playing.