Additional ideas:
1) Red weeds need to respawn ( maybe this is just a bug but I've gone 20 in-game days without them respawning even after removing the leftover stems)
2) Possibly the option for a mini map
3) Improving multiplayer frame rates. Example: Lighting drops frame rates significantly in multiplayer
4) Making weeds float. Seeing that weeds don't respawn, I hate chopping down a weed and half of all of my logs drop into the pond and sink to the bottom, making them unable to collect and use
5) Possibly a technology tree that unlocks using research science that allows the user to make use of electricity. Electric opening doors, light switches, refrigerator to store raw meat so it doesn't spoil, stuff like that
6) Some form of teleportation or fast travel
7) Scab upgrades. Maybe things like sonar or radar that picks up when insects are nearby.
Night vision technology?
9) Hang glider made out of insect wings?
10) Zip lines
11) Ladders. 2 kinds: one kind made out of sprigs and the other out of woven fiber. Climbing ropes?
12) Square floor piece with a round hole in it so you can drop in.
13) Also a pole you can slide down from high levels stacking them with sprigs
14) Climbing equipment? Equipment like clawed gloves and boots that allow you to climb up plants/wood
15) Grappling hook?
16) Bioluminescent armor that makes your entire body glow at night. Possibly crafted from fireflies
17) Larger hitbox on arrows. Allowing the user to pick up the arrows as long as they can point their cursor on the Arrow location marker. So many of my arrows get lost underneath things I can't reach
18) Smoke grenades? Not something that's overpowered but basically a grenade that explodes enough gas so that if you're in a battle and you're losing you could get away
19) Moore custom marker symbols. This is especially noticeable on chests. Unable to use the water symbol on chests which would come in handy for sorting out sap, nectar, and honeydew. And more colors as well
20) the ability to craft more items with the current list of available items. Spiked shield made out of thistle needles and an acorn shell?
Loved all of your ideas for the most part. Just thought I'd add some of my own to see what you think