Yup i would say so, increasing your health means you take more damage before you die and also increasing your eve holding capability is useful especially when your being bombarded by splicers etc.
See I'm in two minds for the reason that I never die because I always have 9 med kits. I just reload instead of respawning with a ton of lost ammo.
The spider splicers are about the only thing so far to give me trouble. I hate the little *******.
I've upgraded the plasmid slots to four, do you get options to buy more slots for the other skills, like hacking? Havent found anywhere yet.
Neptune took me another 3 hours

Just about to start smugglers hideout. All 38 audio files so far.