For Swiftcast, I think the problem is the same as for Bene: supposed to be insta but not so much. Or better, the cast is instant, but if you cast the skill right after vs waiting a second it won't work. I learnt to wait a moment after casting it, between the skill, and it sucks.
Also...anyone getting swiftcasted skills interrupted? Swiftcast-Raise-Interrupt-lose swiftcast. Wut?