The two things holding this card back from being in the upper echelon of cards in this set are that it is uninkable and that it doesn't do anything the turn it is played
Combos Ariel and Look At This Family can be amazing, but another option is using Sebastian Court Composer with another 3-ink character to sing it
Skyfire Phoenix I really want to like Skyfire Phoenix
The other downside to this one is that unless you can remove it, you are obligated to pay the life and draw a card, so it is possible to lose to your own Phyrexian Arena
Kaito, Bane of Nightmares A strong player in the Dimir control and tempo decks dominating Standard right now, Kaito, Bane of Nightmares does it all
Subsequently, even though Ketria Triome is a fairly modern card, its $17 value may fall by a few dollars, at least over the coming months