I don't know if anyone else has this difficulty, but I was having difficulty seeing resources/materials due to its color and blending into the biomes' backgrounds, especially in the swampy biome (Boxcar Bayou?). It's as if the color palette is just one color gradient instead of multiple. Like the "water" from the swamp could be a little blue-r to show that it's water. My friend and I thought it was some sort of poison that needed ores to build a bridge instead of wood (like the lava biome in U1).
The materials should have a more contrasting color to make it pop out and differentiate itself from the biome to indicate where it is. There is a colored outline when a player is next to it and/or interact with it, but overall it was hard to see.
The new iron ore design sometimes confused my friend and I when it shifted to the night cycle. We weren't sure if the material was still a rock or not until we tried to pick it up, and it was made harder that the color of the ground and the iron ore itself were a similar (or the same) shade of color. I suppose we're still used to the iron ore design from U1, and maybe we have to get used to it...
Speaking of material designs, I think that when chopping trees or mining for ores, there should be stages of how many remaining hits that are left before it breaks. In U1, you could visibly see the rocks and trees get smaller and have clear semi-demolished state when leaving it to do something else. For U2, we couldn't really tell at what stage the tree/rock was in since it didn't really change in appearance.