I was just thinking of the attack power, and I'd keep it as daily.Most definitely 4E. Your suggestion of TotFS is in place of the Satisfied concordance rating additional power, right? Are you suggesting replacing both the encounter and daily powers with TotFS? As it stands, when Satisfied, the staff bestows an encounter fly speed move action and a daily close blast attack power. Does swapping both of those for an encounter area attack power (and TotFS is arguably somewhat weaker in effect than the daily) seem well balanced?
The invoker/wizard in my game has the Rod with 6 parts, and TotFS, and (as an encounter power) Thunderwave. With an invoker's WIS, Thunderwave gives huge push. Gust of Wind has better area, I think (cl burtst 5 rather than 3). TotFS gives reasonable AoE (a burst 2), a movement-related debuff which overall is weaker, I think (slow, rather than a decent push) but an ally boost. So in lieu of the burst push you get a burst slow plus some ally-movement. I think that's reasonably equivalent.