Very few rares stay over $10 unless they are cross-format stars or staples, so whatever this hype is, you want to be feeding it, not holding and hoping
If you count up all of the reprints valued at $3 or more, you'll see that Commander 2018 averages four a deck, while Commander 2017 had 6.4 and Commander 2016 had more than eight, which means the number of valuable reprints has been cut in half in two years (while MSRP increased from $35 to $40 at the same time)
If you are using things like the Eldrazi that don't stay in the yard then you need discard outlets that are cheap or free so that you can use it and the Shallow Grave or whatever at the same time
Illustrated by Svetlin Velinov Standard Not Legal Alchemy Not Legal Pioneer Legal Historic Not Legal Modern Legal Brawl Not Legal Legacy Legal Comp
Note that this doesnt care about who controlled the creatures that died, so you can throw a bunch of tokens into your Viscera Seer to set up a huge swing of card advantage
Vampiric Tutor is the next most exciting, which will be worth somewhere in the $50-$60 range out the gate