Stan Lee writes these stories with such enthusiasm, it’s hard not to get involved with them… even when there are glaring continuity errors (Lee has Heimdall taking the assignment of guarding the Rainbow Bridge after Thor’s come of age, when just a few stories earlier, young Thor is on the bridge with an already assigned Heimdall).
The first couple stories feature Odin, which is a bit of a problem, since he’s all powerful and isn’t much fun to watch. His fight with Surtur, however, is fun to see. Kirby’s art’s strongest in that story. Maybe because the outfits aren’t so silly yet.
The young Thor stories, those featuring Loki, are annoying, as Thor is constantly duped by his evil brother. That infinite gullibility is one of the things, I think, I didn’t like about the character as a kid (and therefore, didn’t read much Thor).
Again, Lee makes it work.