Antiarc et al.,
I just want to say, I love the vision behind this project. I've been playing around with Omen & Threat, and attempting to get some of my guildies to start trying it. I'm a healer, so threat isn't as big an issue for me, but my old main was a hunter, and I'm still used to watching it.
Most of my suggestions have to do with the pull out threat bar:
1) It would be nice to have some sort of way to easily configure the bars while out of combat. I know you can kinda do this with 'show test bars' but it didn't seem to work well for me. Thinking like the configuration mode for PitBull.
2) It would be great to have the bar automatically track your aggro in relation to the tank, aka aggro target (as I write this, I realize this will be problematic for bosses that do secondary attacks and momentarily switch targets... but still possible)
3) When pulling out multiple bars, it would be nice to have some way to keep them all the same dimensions. I accidentally resized one while moving it and (while I can eyeball it) I know in my heart it will forever be the mis-sized bar.
4) The behavior of the bars seems a little wonky when you're not yet on the aggro list. As I sat back waiting to heal the tank in a heroic, my aggro on the single threat bar kept going from ~15% -> 0 over and over and over. Presumably it was repeatedly trying to animate from my last known threat to a null value, but it should have just displayed me at 0%. As soon as I threw a heal out, it would stabilize.
5) From a display point of view, your addon is beautiful, but it would be nice to be able to move some of the sub-components. Mostly, my layout is pretty trim and functional, but Omen has a lot of things that sort of stick out or above or to the side. It would be nice to (at least have the option to) move some of them into their parent frames. Such as the 'Omen' at the top of the threatlist, the version #s at the bottom of the threatlist, relative aggro at the bottom of the appropriate bar, etc.
That being said, congratulations on a particularily awesome addon, and thank you for your contributions (past and continuing!) to the community.