ThatGuyThere
Explorer
Honestly, the only things I've found useful in Trailblazer are already part of Pathfinder's core.
I might look into to combat reactions, but that's about it.
I think you're both praising Trailblazer, and selling it short, there.
It's a solid product. It pokes and prods the rough patches of the 3.5 engine, and reviews some of the base assumptions. It's an <interesting> read, even if you don't play Trailblazer, directly. (The same as, even if you continue playing 3.5, it's worthwhile to read Pathfinder.)
On the other hand, it's incomplete, I'll grant - it feels a lot like a "patch" instead of a "new game". It doesn't replace the PHB / DMG; it refers you back to the core rules for a lot of parts, and leaves a lot of it to (essentially) DM's call / Rule 0. I'd prefer it if there was a hardcover, hand-the-book-to-my-players full Trailblazer book with spell lists, spells-per-day lists, etc, etc.
I would like a "complete" Trailblazer (including a monster book, in hardcover!) to hold next to my Pathfinder Core Rulebook.
And then I'd press the books together in a vise, and take the best ideas of each.