Redefining Hail of Blades

Hail of Blades is currently a niche keystone, which on the surface is fine (ex: Glacial Augment Tahm Kench, Predator Annie, Unsealed Spellbook bot lanes) however its use cases leave something to be desired. Here's some issues and random suggestions.

1. Direct Competition from Electrocute: As a Damage focused Keystone Electrocute seems to perform better particularly when abilities are in the rotation, possibly leading to FOMO.
2. Target Champion Pool: HoB doesn't have well defined users like Electrocute for spell-based assassins. AS is part of so many kits with different uses. A few examples: Xin Zhao to get faster knockups, ADCs to front load damage, or Assassins as an electrocute replacement.
3. Less Visual Feedback: The VFX for HoB shows when its available, this runs contrary to the design philosophy of giving feedback on use and also places the graphic on the user rather on the target (Then again so does Lethal Tempo which is Yellow's Direct counterpart to HoB).

Possible changes:

1. Direct buffs: Helps in every use case, makes a case to sub Electrocute for AD assassins, but still lacks defined identity aside from a sheer stat boost.
2. Adding Damage/Pen on Hit: Flat or AP/AD scaling Damage on hit increases burst and makes it attractive to burst oriented assassins or front loaded DPS. Also adds visual feedback by numbers.
3. Moving the CD from Out-Of-Combat to dealing damage: Depending on the numbers this can favor either assassins or DPS. I'd imagine that this would be best suited for extended fights where multiple rotations would be desireable over a single electrocute proc, thus defining HoBs niche while rewarding opportunistic/patient players.
4. Adding Utility (My personal favorite): Red hasn't had much in the broadly useable utility since the removal of stormraider's surge, adding in-combat MS/slow-resist could provide meaningful ingame useage which thematically separates HoB from Electrocute. This comes at the risk of abuse cases where Ghostblade/HoB assassins become too much for even the most elusive of targets to escape, and the worry that Phase Rush and HoB would be too similar even though they should have different use cases (Xin Zhao being a possible exception).

Shout out to Riot Rovient for carrying/clutching on Kayn and pointing out this issue to me also please don't take this as a "Rito Pls I know how to do your job better than you" post.