I'll post an updated screenshot as soon as I'm home.
To your points though;
1. When I'm healing that target cast bar is removed and I just use the one on Ag_uf because it's easy to read and I generally know when a mob/boss is about to cast something important due to DBM. I may enable it for more important cast bars like when in Amber Construct but I doubt it.
2. Also removed the black border on PA timers already.
3. I've tried central raid frames before and hated them but I do know the obvious advantage.
Another thing; does anyone know a way to skin DBM timers without TukUI/ElvUI etc.? I think they're really ugly in their original skin.