Infinite gold is an issue, no matter how much of a chore spamming the 2k is, you're going to get everything eventually without spending a penny, with the current regeneration that'd still be possible but would take years. Add in something like AW Betty and your Shrine profits will crash down pretty fast.
One important thing about Event maps is that they cost a lot more Stamina than Charisma for the higher-end maps (e.g. 50:7, 90:12, etc.), you'd have time to regenerate a decent amount of Charisma by the time your Stamina goes back up. If you look at something like
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you'll see that you'd spend very little Crystals on Charisma even for a collection Event (granted, the drop-hunts can go badly if your luck is poor).
Also, most of the Extreme-tier dailies are Charisma-heavy, so instead of being a trade-off (farming high-end dailies vs grinding story maps for XP) it becomes a non-issue. And then there's the Awakening maps, 90 Charisma and 0 Stamina.
I think we're all aware that Charisma and Stamina are just there to slow progression and tempt people into spending Crystals and I do feel like they do their job quite well.
