I mean really damn hard.it seems that you take more damage,your non-psy attacks do little damage and because of that I feel more afraid than playing as a marine.

That's why I used to edit this game before I played it, to make it harder since I use bullets and blasters. It's been a loooong time since I've done that though, which is why I started that other post about Shocked. I don't even know if that would work with the new version GOG is selling.

yeah, but imagine an OSA guy later in the game, wearing the forever lasting powered armor with psi shields active, strength boosted to max, adrenaline overproduction active, obliterating everything with one swipe of the psi sword while shrugging off all enemy attacks laughing.

that'll be your reward for the tough beginning.

You're imagining it. SS2 uses a classless RPG system, so you take and do exactly as much damage as in any other initial career choice.

The true difficulty in being a Psi user comes from managing the various abilities and tiers effectively. Juggling between 5 tiers of abilities and whichever weapons you decide to utilize can be interesting, especially when many situations
in the game demand reflexive decisions. Also, psi hypos are one of the most costly resources in the game, though with use of certain psi skills, one can effectively replace anti-toxin, radiation, and med hypos all with the psi hypo. As voodoo47 said, using psi becomes uber-powerful and rewarding in the late game, but the early game cost to invest in psi can seem pretty steep.

If you feel like you're taking more damage, maybe you haven't put as many points in endurance? The difference between having 1 level of endurance vs. 3-4 is significant, so for anyone having trouble with taking a lot of damage, spending some points in endurance can be a huge boost.

not on the hard and impossible difficulty though - a mere (and quite costly) 3hp boost for each level, probably not worthy of upgrading beyond level 4.

On hard, maybe not. On impossible however, 3 hp per level is HUGE considering you start with around 10. So putting endurance to level 4 effectively doubles your health pool.

My current built is an OSA and I having a good time. I've maxed out END and are just one tiny upgrade from fully
upgrading PSI. I have Cryo and Pyrokenesis as offense. Most creatures go down after one blast of the Pyro while some others need to be taken down with Cryo and therefore takes about two hits. The only reason to why I am dying now is because I get careless.

The trouble with Psi for me is that so many of the things it does can be done permanently through buying stats and skills.

Maybe it would be a more economical way of getting those things, but the fact that there is no fast or easy way to switch between powers is a drawback for me.

I also wouldn't want to feel rushed to get the most of my powers while they are active.

On the other hand, you have a psi pool and psi hypos, so it would seem optimal to find a way to get some use out of them.

And if you intend to use psionics at all, starting as an OSA gives the most training in terms of equivalent cybernetic module cost.

Making my way through the game for the first time as an OSA on Normal. Wrenching monkeys and hybrids is easy enough, but turrets, bots and droids really started kicking my ass on the way through the Cargo Bays. I eventually got through it all with 2 HP and 0 Psi left. I ended up raiding every box I could find for alcohol at that point! Survival horror at it's most unexpected.

I blew a lot of mods on repair and energy weapons to get the broken laser pistol to work which fixed the droid problem. I probably shouldn't have blown more mods on maintenance and using up most of my maintenance kits to patch it up. Probably should have gone with Standard weapons for versatility to deal with suicide bombing enemies and turrets but hey I'm going in rather blindly not knowing what's behind the next door. I'm saving the standard weapons for a future bad ass marine playthrough!

It would not be terribly difficult to complete the game on Normal with Standard Weapons maxed and nothing else at all. Standard 1, even, if you could find enough pistol ammo. Then again, I haven't yet seen how much voodoo47 nerfed standard weps in his ADAOB mod. I'm sort of waiting for the SCP.

Playing through at least once without standard weapons is probably a good idea just to force yourself to experience the game's many other tools.

I couldn't resist and started over with another OSA concept in mind: Standard Weapons focus but with some utility from psionics. There is something badass about bending your will to hold a gun perfectly steady and controlling the flow of adrenaline for delivering those hard blows with the wrench. Hive minds and AIs can never match the super soldier of the future when it comes to ingenuity and battle prowess!

On the contrary to most rpg like game, you shouldn't go with the optic as I play a mage in your first playthrough.
Also I discovered very fast that you must focus on a few select "spells" rather than go with a full spell book
In terms of fighting. Then get utilities spells to reduce alarms etc...

Also have a range and melee weapon ready.

Go hide when healing. I usually used hit and run tactics with that kind of build... Enemies are slow at best...
At worst find a bulkhead or a lift.

With those strategies you can smoothly until you get good gear (also try to stock up on those worm piles they really get usefull later. Just drag a beaker on them)

If you're OSA, or Navy, or any kind of build, just go wrench-style. Just because you're OSA doesn't mean you have to use your cryokinesis. I save that for turrets and cameras.