What works well:
- Some logs and planks (specifically Oak log/plank and Birch log)
- All of the leaves
- The text and GUI in general
- The grass top texture (and the random CTM for it)
- Sand and Sandstone (specifically 24:0, not the bricks)
- Biome coloring
- Bedrock (it has a neat animation, pretty cool and unique)
- Stone bricks (they're all really nice in my opinion, especially the CTM for the moss stone bricks)
- Hardened clay
- Bed (yay quilt!)
- Chests, Torches, other wood-based items)
What doesn't work so well:
- The colors of the pack in general: in some cases, I like it (see list above); in most cases, it kind of just seems willy nilly, and everything is super-duper-DUPER high contrast, almost too much for my personal tastes
- The patterning on many blocks, such as dirt and stone: I see the top grass, and how subtle and pretty and soft it is, and I wish the stone and dirt matched that style; but instead they're these hard obvious patterns. Sad face. Maybe use more CTM to randomize and smooth things out.
- The ferns: Again with the high contrast thing.
- Theme: Or rather, the seeming lack there-of. I mostly just see high-contrast, old-school stuff, but without a general guiding theme that's apparent. Even packs like Summerfields, which you can't classify as "Medieval" or "RPG", have a theme of "summer" or "warm" or "rustic" or "soft". Try to unify everything so it fits some sort of very apparent theme for the user.
These are my general impressions when I boot up this pack. Lots of things I really like about it, and a few improvements I think could really help this get where you want it to be. I hope this helps!