Yorick Passive Change Idea
A problem that I often run into while playing as Yorick is how difficult it is to raise ghouls outside of laning phase. Yorick's ult does raise ghouls, however it has one of the longest cooldowns in the game so it is often unavailable for skirmishing. This long cooldown, coupled with the fact that most teamfights do not start where Yorick has easy access to graves (for example, in the jungle) means that Yorick is often unable to fully utilize his kit.
To solve this, I suggest changing his passive, which has a low impact at nearly all stages of the game.
Currently, Yorick's passive raises a grave for every 12/8/4 minion that dies near him (at levels 1/7/13). This ability is not very useful in lane and does little to help Yorick raise ghouls out of laning phase.
My suggestion is to change yorick's passive to the following ability: Sheperd's Call: Every 30/20/10 seconds (at levels 1/7/13), Yorick stores a grave in his cloak (max: 3). When Yorick has stored 3 graves, his next cast of awakening (second Q cast) will consume these and any nearby graves to summon up to 4 mist walkers.
The number of graves that Yorick has stored would be visible underneath his mana bar, like Jhin's ammo. The idea that I was going after was to give Yorick better access to ghouls outside of lane in the mid/late game without significantly impacting his ability to raise ghouls in laning phase.
Let me know what you think about this idea and/or your ideas to change Yorick (if you feel he needs any changes)!