I've just been considering that lately, the only Shadow Spell I see players use (Primarily in PvP and PvE) Is Shadow Shrike. I have wondered lately if KI would introduce either a new spell (Maybe for Life or Death) that destroys a shadow pip and deals damage - similar to mana burn- but is not Super OP. Or, consider changing the Shadow Seraph and Sentinel to something more likeable for players. Personally, I would never use the Seraph due to the increase in incoming Damage. Changing this to -25 incoming damage may be the persuasion to somewhat counter shrike.
I don't see shadow pip manipulation any time soon. When you see Shrike go up, that's the time to burn, stun, juju, weakness, plague, dispel, etc Anything that prevents or delays attack increases the backlash, and since shadow pips are rare,. it's usually not too hard to anticipate it coming.
I agree with Gemma, there are loads of counters to Shrike already. And I also disagree on only Shrike being used, I see Seraph and Sentinel used regularly in PvE by healers and tanks, exactly what they were designed for. What I don't see is shadow creatures being used. I liked the idea when it came out in test, but it really isn't worth it for the spells. I have also never seen anyone use the newer shadow morph attacks except a few people trying them out during week one. Did anyone really bother using training points on them?