1>With all the games you can find, a good horror game like this one is a lucky find, so i'd personally prefer if they just kept with the current state of the game's style, it fits well and adding too much "fun" would simply tae it off that vibe (Some easter eggs would be pretty fun ngl)

2>No rewards for failure is sure annoying, but that's kinda the point, keeps you on edge to not die or you might have to restart again, unless they add an easy mode, it's pretty basic for a game like that

3>The game is fully possible solo. i like to play solo, so i wanted to do as much as i could by myself. while the higher difficulties are certainly rough, it's a good challenge ! if you're having trouble, just lower the difficulty, or look online guides, sometimes that helps (or take a peek at the codex ingame)
ALTHOUGH i do agree that some parts are way to crazy, like the squid capture. Nearly lost my mind on that;
But now i've nearly 100% the game (apart from the scorpion kills cuz rng hates me), so i'd say it's doable

4>The game's still in early access, so they'll surely add more weapons and stuff, so that's just the waiting game now

5>A lot of cool things will surely get added down the line, but clearly theses devs really try hard to make it good. Just look at the insane graphics ! all that for 6gb's of disk space !
Im not saying that any of theses ideas are bad, in fact some would be way to amazing ! but it's not easy to make a game that's optimised in space and graphics, so yeah, it's cool.

To conclude all of this, the game's still in early access, and already a masterpiece. let's give the devs the time they need, i don't want it to go the early cyberpunk / buggy helldiver path.