As Blood, your best active threat tool without * is Heart Strike. You want to use DRM with DS to turn over runes and spam the heck out of it while maintaining diseases.
That said, it is possible for DS to do more threat on a single target than HS, but it requires certain criteria to be met. Your only listed character is your warrior (epic t2 set by the way), but I'll throw out some of my numbers to give you an idea of what I mean.
My HS hits for about 2400, my DS for about 2600 both non-crit. For the moment we'll ignore that HS has a 3% higher crit chance which will bring their average threat per swing about even. That means if I am at full health, the damage threat only of the two, HS will always win. However, if you are on a single target, DS heals for 15% of your total health, and that healing causes threat, which is unsplit on that single target. With my total raid buffed health, without Vamp Blood, DS heals for about 6900. So, to find the total threat done, here's the math:
HSx2 = 2400 x 2.0735 x 2 = 9953
DS = (2600 + (6900/2)) x 2.0735 = 12545
But bear in mind that: only effective healing counts, overhealing will reduce the heal portion threat, and healing threat will be split over all available targets.
So, the answer is, to get best threat:
1.) Use DRM to spam HS as much as you can
2.) Use DS whenever you can make most use of its heal, even if it's using Death runes.
Using Death runes to cast DS will not spend them, it will just refresh them as Death runes.