I've been trying to get into combat, I splashed some of my credits on a Vulture (figuring it would be excellent for combat)
and I added some gimballed weapons and upgraded most of the systems but oh my life, I am terrible.
Yes, I keep the throttle in the blue zone almost all the time but even so, I cannot stay with anyone during combat, I get behind them and get a few shots in and they simply out turn me and I struggle to get them in a firing position and when I do its 1-2 secs of firing and again they out turn me.
Did I pick the wrong ship or am I utterly useless?
If I had to guess, I would say that most likely:
You are starting your turns too late, and perhaps in a not-optimal direction as well.
You've seen Top Gun and/or Star Wars, and are applying that type of flying, instead of using all of the tools in your bag.
You are not turning on as many axes as you could (and should), an extension of the previous point.
You are maintaining too close of a distance in an atmospheric-style circular turn fight, which can lead to what you describe.
I'm not saying these things to say that you are bad or make fun of you - based on your description, these seem like the most likely reasons, and they are common. Also, the AI is quite adept at using the Thrusters, so if you are not, then they probably are indeed out-turning you. Gimbaled weapons or Turrets will help, but they do less damage, and they are a Band-Aid to the issues you are having. If you want to get better at Combat, you really need to resist using Band-Aid fixes. Get out there, learn, blow up, learn some more. Alternatively - find someone who is good at Combat, and see if you can do a Multi-Crew session with them (or a Wing) as an observer, so you can see what they do, and why.
Is your Vulture stock? I'm not talking about Engineered or not, I'm talking about standard equipment upgrades, or did you just put some better weapons on it and head out? I'm referring to the Thrusters mostly with this question.
Edit to add: If I remember correctly, the PS4 is capable of recording gameplay. Record a few fights, then watch them later. You will be able to see what you missed, and you will also see what actually happened, as opposed to what you think happened. You might be quite surprised at just how far off our memories are from how things actually happened, especially in reference to reaction time. There might be quite a lot of valuable lessons just from sitting back, and watching your own play. This is something that would likely benefit most of the people that play this game, not just you specifically.
Riôt