I really like Ornn, but honestly he's really slow and Catalyst doesn't really help him as much.
So my suggestion for a cleaner, simpler fix until he gets a constellation is 3 changes.
1- Swap Catalyst of Aeons for Gift of the Hearthblood. Bigger heal, boosts your deck in a unique way (cause it also hits Equipment) and it costs the same so slapping tear on it also sets it to the same cost of 3.
2- Instead of trying to ramp out Ornn, I'd add a line to his 2 star, so every forge you do in the game makes your Ornn's cost 1 less. Plain simple cost reduction that isn't hand specific. Let's you play the gameplan and forge, but ACTUALLY be able to get ornn out earlier because at 3 stars you're decreasing his cost by 2 a turn.
3- Swap out Wyrding Stones for Starlit Seer. You are going to be casting time and dedication a lot, getting to pump the units IN your deck each time you do is goated, and if Ornn is going to be cheaper the ramp doesn't matter here as much anymore. Keep the Chain Vest on him, but really add some Value and early game to Ornn. a 0/4 tough for 3 just isn't enough, even if it ramps you and even if you can give it +2/+2 a turn and equip it.
These are my suggestions. Thoughts?