So I like the idea of acquiring Jax to try and convert him into a starter. As for Vasquez, he may be a defensive upgrade but he's still going to be a negative on offense. His offense has gotten worse year after year for 3 consecutive years now so I'd count on that trend continuing in 2025.
I highly doubt the Twins would make Jeffers available but he would be fit on this Cubs team. They're lacking offensively an catcher is the 1 clear spot that can be upgraded. The free agent options aren't too appealing though so Hoyer is going to have to get creative.