I kind of liked Temple of the Oven King, it was satisfying to speed through the old areas with your new items. Still, Spirit Tracks had the better phantom dungeons. PH suffered from bland music and visuals + boring overworld design, while Spirit Track's train travel got aggravating quickly.
I haven't played ST yet so I'll keep my expectations in check for the train travel, thanks for the info on it. PH didn't have the most memorable OST but I did find its oceanic travel and mix and match ship part aspect pretty fun. I liked the little points of interest to check out and the game world felt surprisingly sizable for having only four map regions (echoes of Termina, there). Charming NPCs as well. Dungeons were solid and the boss battles were pretty spectacular. Some of the islands had clever minigames of some decent difficulty, especially that maze. My only real gripe off the top of my head was it was unrealistic or overly cumbersome to get all ship parts without DS connectivity, if I understood correctly. I suppose that's a hallmark of the days DS local connectivity was easier to come by.