Problem with this tier list is that is doesn't/can't consider the other powerset taken so its about useless to grade them as such. Controller with elec affinity will have their hands full unless they take a more passive control set, or neglect elec's potential, but that's not a problem with the set itself. A defender elec ont he other hand can give elec proper care and dps inbetween buffs/heals then elec becomes Tier 1. Anyone who says otherwise doesn't know how to play it. You can't take into account the 'traps' you proposed because every single set has those same traps. Over buff, over heal, or not doing them enough. That's a person's ability to play the set and not a reason to diss the set itself. Its a lot of stuff with elec affinity and if you take them all then you have ot learn to manage. Same with a fire/kin troller, its overwhelming if you don't know what to do. Kin itself has a high skill threshold, you can't just spam the buffs/heals, you have to make sure your team can get them. And if the person needing a heal that's not by an enemy then your heal is useless.
FF in comparison is a Tier 2 at least, straight buffs and some cc when used right, especially in tunnels. But even if you only take the defense shields, this allows you to focus on your other powersets. Works great for a corruptor or controller. Symphony for example can focus on cc'ing everything with fear, debuff procs and roots between stun/holds. The shields work passively, coupled with leadership powerpool makes it a walking cc buff bot. Right mix of power pools and the build itself can be tier 1.