In battle, I could use Cherry Blossom Snow Storm Technique to cause a very lethal situation with the use of very little chakra. A regular explosive kunai on its own is already pretty lethal, so hundreds of them is logically even more so. Offensivey, a good way to use this would be as you said, to bind or distract the opponent whilst using this. One just needs to create a situation where it is hard for the opponent to counter this, or even see it. Hidden in the mist could also work in some occasions. To defend against this, a win technique, or fire technique could blow the paper bombs away or even destroy them (burn or rip). Another bomb tagged kunai could prematurely set off this technique, and shuriken could deflect the kunai. I find this technique very interesting and somewhat useful. I love using kunai with bomb tags, so I naturally find this technique awesome! Question though, is a single kunai thrown in the beginning with the pouches, or is it multiple?
In battle, I would use the Haze Clone Technique in combination with Underground Fish Projection or Hiding Like a Mole to hop in and out of the ground and attack my opponent as the Haze clones do "combat" with the opponent (even though it's not actual combat because Haze Clones are intangible.) Offensively, once again, I would use this as a set up to offensively use Underground Fish Projection or Hiding Like a Mole. To counter this one could use the Sharingan because that can realize that the clones are fake, one could engage in combat and then realize that it's a Haze Clone because it was not effected at all, etc. Because the clone's are intangible, I'm not sure if there is a real way to "destroy" the clones though. I find this technique interesting but not all that useful (at least in most situations). I can see it being useful for crowding an area then getting underground for a surprise attack, but I can't see Haze Clones being all that useful, though every technique has a time and place.