I do think the Dante nerfs were excessive and should be dialed back somewhat, while DE takes a closer look at the core problem behind (some) of the complaints.
For instance, instead of heavily lowering Dante's Overguard accumulation, fix the problem people actually have with someone using Dante in their group - it affecting gimmick mods or abilities that require the Warframe taking direct HP or shield damage.
Eg: Rage. Since its inception, DE has added more and more mechanics that completely prevent or heavily restrict the usefulness of this method of energy generation. Overguard being the latest offender.
Shields, Overguard, Ironskin, Adaptation, etc. Even your Warframe's own armor stat negatively affects the Rage/Hunter Adrenaline. This has not changed, and I think it's high time it does.
Rework the abilities' and mods' function to something that works even if you're affected by an extra protective layer that may come from another frame. Nip the problem in the bud, instead of just waiting for the next support/defense frame to show up and the problem repeating itself once more.