I personally like the names bounty kill, blood pact, or mystic contract more, but I like the idea. Also for clarity change the text to "Imbue an ability with permanent spirit power. On hero kill reset imbued ability's cooldown."
Trickshot makes Holiday 3 useless, so no on that, but I like the first item.
Second item is a little OP, but I think an upgraded mystic shot could be cool, at 6400 though.
For the last item, I like the idea, but make it a small added damage over time on hit instead (like toxic bullets for...
Could be an interesting item, but needs to be 6400 cost. Also, it can't exist at the same time as glass cannon because then you would be doing +200% on paradox, for example, for 12.8k, and just be one-shotting people left and right. I think if you make it base fire rate -40%, acc while firing...
Volocity, I agree with, but some things like bebop and lash ult would destroy game balance and just make them gods in team fights. Other than paradox it is way to much, and even for her it is too much.
My same thought with someone's base tp idea (like league). It would have to be 6400 if not more, somehow, to make it not a must buy, but by then it would not be worth it.
I think this would be interesting, but the cost can't be 1600. It would just become a must-buy item that everyone would always use. In addition, the ziplines already do this style of mechanic, so I don't know how useful it would be if balanced at like 6400.
Update: I believe it has been patched. As I was typing, I finished the update, and it no longer works for me. (haven't tested abilities yet, but I assume that too)
I can't record it on my end because I am on a laptop, but I wanted to mention that this same input combination can also be used to instantly change direction while already dashing.