For survival, we want Runic Empowerment to only proc Frost, Unholy or Death Runes for us so that we can use these to fuel more Death Strikes. Unfortunately, Runic Empowerment on it's own will not differentiate between fully depleted Runes and can return Blood Runes - unless you game it. Here is how:
This is the base layout for the Runes. I am using a block format since that groups the respective Rune pairs visually.
We have to create Rune states where only one one of our Blood Runes is on CD* but atleast 3 Death/Frost/Unholy Runes so that our Rune Strikes can only proc the Death, Frost or Unholy Rune. Most of the time, you will have all 4 of these Runes on CD because Death Striking puts them on CD 2 at a time. Typically, it will look like this:
A Rune state that is ideal for RE gaming because it will only proc Death Runes
Every Rune Strike now has a 45% chance to proc a Death Rune and no chance at all to proc the Blood Rune (because it's pair is still off CD). Note that Runic Empowerment always has a 45% chance regardless of how many Runes pairs you have on CD. It doesn't matter that 2 Death Rune pairs on CD - the chance is still 45%.
In this particular scenario, we now have 4 seconds to use our Rune Strikes and no longer. Once the top row of Death Runes cools down, we have to start anew and try to recreate this Rune state again before we continue using Rune Strikes.
*While you can simplify things by never using Blood Runes at all, I recommend against doing this. Not only is this a waste of DPS but you also lose 10 RP per unspent Blood Rune. Practice with atleast one Blood Rune always on CD and I promise that after a while you can game Runic Empowerment so well that you will even be able to put both Blood Runes on CD at once because you know you can afford to wait until one has cooled down before you use Rune Strikes - all without capping on Runic Power.