3 CMC specifically is interesting on Trophy Mage because it hits a lot of combo pieces:
Metalworker/Staff
Rings/Monolith
I wasn't playing staff before, maybe this makes it appealing enough? I'm not sure. There are also other considerations like Grand Architect etc. I'm not 100% sure I will include this card (definitely worse than Trinket, Fabricate) but it's something to consider.

Scrap Trawler is super interesting, definite auto include imo. Junk Diver and Myr Retriever are usually returning an artifact with CMC <3 so it's an upgrade in that sense.

Works well with:
Tinker activation (Arcum, Kuldotha, Reshape/Transmute)
Possessed Portal Trigger
Blowing up a board with Disk/Ostone
Tangle Wire fading away
Smokestack sacrificing things
Mindslaver / Memory Jar popping (Kind of a nonbo with Jar because the returned artifact will be exiled until EOT in the Memjar pile, but still)
Skullclamp Sac
As a very weird line if you desperately need to rebuy a critical expensive piece you could tinker up Spine to destroy itself

I still think that Spheres are the way to go in terms of disruption, so it's not worth building the deck with a ton of eggs & lotus petal type cards, but these definitely work the best with the Scrap Trawler.