All those changes sound incredibly over tunned.
you want 2 dots with the AOE being a gain on single target. Eukrasian Dyskrasia 40 potency for 30seconds =400 potency full duration. reducing the dot duration on the single dot is just adding to the fact you just don't want to long cast(dosis)?
reducing the CD on Phlegma just adds more instant cast so you don't want to long cast anything(dosis). Reducing CD on Psyche is just OP and unfair compared to the other healers
giving Toxikon a proc on dots instead is stealing right from Bard but also again making it so you don't have to long cast your Dosis while you also want it to do more damage than Dosis...
but you think it's ok if your Dosis does next to no damage to compensate this? you would have to make it do like 100 potency for this to be at all fair and its not practical.

But of course even if you went the other way and reduce the potency of Phlegma, Psyche and the Dots to compensate the changes it would still be busted as you rarely cast Dosis. it sound exactly like SB Scholar, which even as a scholar main I don't want to go back to this.

Keep in mind Sage got the best new damage skill out of all the healers, you require no previous skill to activate it absolutely free to do insane damage to single and AOE mobs.