I'd also recommend focusing on only 3 weapons in a single playthrough. I found stasis upgrades to be the least useful something only to take when you don't know where else to put your nodes. Once you do that, either focus on your rig or figure out what other weapon you like. I would absolutely recommend upgrading your plasma cutter first figure out the path that will get all the damage upgrades in the shortest number of nodes and follow that one. In my experience, the difference between a fully damage upgraded gun and one that isn't fully upgraded is ridiculous. I don't plan on going for the Plasma Cutter only playthrough yet because it's just my first run.

Is that just straight up 2 seconds? On the other hand, upgrading the Plasma Cutter might also help with the damage prevention. I have no reference for how much longer 2 points of Duration will give me though. An extra 20 points in Energy would give me another shot I presume. I'm not sure how often I should be using my Stasis, but it seems like I should learn to use it well pretty early on. HP seems like the obvious choice but I'm wondering if upgrading my Stasis Module first will end up preventing me from taking damage in the first place. I am wondering what I should focus on increasing first for survivability: Rig, Stasis Module or my weapons (the only one of which I have is the Plasma Cutter currently). I've read that I should try to keep at least one Power Node on me at all times in case I run into a locked door.

Specifically, this is a first playthrough on Medium difficulty.

Dead space 3 plasma cutter upgrade