Fairly simple idea for how to make Sonic Resonance a little better and in particular how to fix Sonic Cage:
Sonic Cage becomes Single Target Foe -Res, -Spd, and applies the "Sonic Cage" effect for 30 seconds. Moved to tier 1 spot.
Sonic Siphon becomes Single Target Foe -Spd, -Rech for 30 seconds and Self +Regen, +Recovery, fairly strong effects, but only 5 or 10 seconds. If the target has the "Sonic Cage" effect on them the +Regen and Recovery effects become PBAoE Ally effects. Moved to tier 4 spot.
That's it.