I'm honestly content with how SMN plays right now. Do I understand the complaints? Yes. Yet despite that, SMN feels more like SMN than it ever has thematically, has similar punishment for jump phases/downtime compared to its other caster DPS, and for the first time ever doesn't feel like it's sacrificing its fluidity to do any of that. It's not perfect by any means, but I'd rather not see any rotational changes. For the first time since HW, my only concern is the numbers.
Even so, if SE wants to restore what people liked about SMN's gains from downtime before, what I'd like to see them do is add charges on DWT/Tri-disaster/Energy Drain (while also boosting Tri-Disaster's cooldown to 1 minute), lock them to 1 charge on instance transition/reset, and only let them charge during combat, akin to WHM's Lilies. I feel that's a good compromise overall. The only other thing would be allowing Devotion to be used by Bahamut/Phoenix if people really think that's needed. I don't feel it is, but the option's there.
Numerically, I'd like to see Ruin II and IV buffed by 20 potency each (basically copy Ruin I to Ruin II, and up the base potency of Ruin IV), a 10 potency increase on each of their DoTs (as it's less problematic to adjust compared to Ruin III), and allow Ruination to affect Fountain of Fire/Brand of Purgatory, Phoenix's spells. As far as I can tell it doesn't appear to right now. If it does, update the tooltips to communicate that.