From the opening intro, the game looked unpolished (probably because of UE3). Lot of pop-in, some weird texturing if you ask me and I got instantly turned off from it when I saw Secret agents shooting at terrorists...in front of their SUV...with no cover. This wasn't a deal breaker for me, but it was kind of laughable. Later on in the demo, when you see Claire getting straight PUNCHED in the face, not slaps, but haymakers, that was laughable too. IDK what I was expecting, but I didn't expect that...lets say...level of comedy in Shadow Complex.
Besides those small things (and they really are small, I'm just explaining why they bothered me) the game just felt weird to me. I personally dislike it whenever developers call their playable Hero character an "every man" because they're clearly not...Jason is

ing beating the shit out of heavily armored guards, he instantly knows how to use a pistol and throw grenades with extreme precision. That's not really a fault on the game because it's how the game is played I understand that, its more of a personal bias. I know it's based on the "Empire" series so if that fiction explains Jason as an every man, then I'm sorry. But just personally, I don't like playing as an "every man" because you never are just an "every man"
For instance, I also disliked it when Naughty Dog first introduced Nathan Drake as an "every man" in Uncharted...then I saw the gameplay and went IDK what kind of people they consider an "every man" but some ninja who can run, duck, hide and shoot and kill hundreds of pirates is not an every man.
Don't tell me the character I'm playing in your video game is an every man, when you give me the ability to kill enemies like I've been trained as some kind of super soldier. Either make a game where the gameplay mimics an actual "every man" where he doesn't know WTF he's doing or don't call your character an every man. I know in a certain cutscene, there's a short flashback where Jason is talking to his Dad and how he doesn't wanna follow in his steps and kill people, so maybe he IS trained but because of the Demo, I didn't get to that so if I'm all wrong, just say so.
In terms of the gameplay, I thought the aiming with the right analog was a bit awkward. It felt like I was controlling a twin-stick shooter that disguised itself as a 2D shooter, but ideally the game only wants you to use the one right stick at a time because you would want to be hidden in cover so you don't touch the left stick...maybe it takes some time, but it felt awkward.
Finally, the thing that most bothered me was how the screen didn't lock during the Tarantula "boss" fight. When the thing rushed me to the left, forcing me to hide in the room where you get grenades, it all just felt weird. I was afraid to come back out because I could no longer see it on the screen and if I did go out, how would I know it wasn't going to just come back rushing again? I think I've just been trained that in most Metroidvania style games, "mini boss" or "boss" fights are going to have the screen lock and you won't be able to move left or right after a certain point and you have to play within the limits that the game has given you. So when the thing moved in and out of my field of view, it forced me to chase it and possibly get hurt by it because I couldn't see it's pattern and what it was doing just felt wrong to me.