Yeah, there's nothing you can accidentally screw yourself out of in terms of collections / progress. Spoiler tagging anything that might be considered a "cool discovery," just in case people want to find things out themselves...
- The fish you can catch on the Island Map are the same as in Pelican Town.
- The special weeds you can find on the forest map just drop mixed seeds, which can be found everywhere. The foraged items and bushes can also be found in the wilderness. Hardwood is always available in
.
- The Geode nodes that appear in the Cliffside map behave the same way as the geodes you find while mining, and you can find all of the ore in the mines
- The Wilderness map's Golems don't drop anything exclusive, mostly stuff you can find while mining.
It's purely an aesthetic / difficulty choice (in that it will be more difficult to build all the structures you want and have room for lots of crops and such, they aren't any harder).