Most cubes are running 11-13% fixing which I think is woefully inadequate and creating an artificial scarcity that ultimately hurts drafting
The lack of any clear labels to take you to your decks immediately is kind of a pain, but as soon as you get the hang of it, deckstats is an easy site to navigate
There are plenty of creatures with those types in Olivias color identity, so theres no shortage of creatures to throw into this deck
Coordinated Maneuver and Osseous Exhale are both great options, too, if a little more conditional
Additionally, upon entering the battlefield, Karrthus's controller gains control of all Dragons on the battlefield, meaning that if another player happens to be using a great Dragon card such as a Goldspan Dragon, that value can be stolen for the Karrthus player