So you asked for criticism, here goes.
First off the size. if you are going to make a ship that size don't even bother with weapons because they will not be as strong or powerful as the Isanth's supplied in the game.
Secondly, nice ship shape towards the back, however you should really try and mix it up at the front. The long flat 'snout' of the ship makes it look like a toy.
As for the colour scheme red and yellow arnt really the best mix.
However its nice to see a bit of logic and I like the cot pit design. I'm also pleased that you managed to fit that many systems onto such a small ship so well done with that too.
My advice is to try and build something about 5-10 times bigger, it will teach you a lot about how you want to build and a lot about what makes a good ship in terms of weapons.
Bit harsh but you asked for it!
I tried to make it small, so it would be cheap and light as a fighter should be. But you might be right about building bigger, since resources aren't that hard to find. My only problem with bigger ships are turrets. Rail Turret Axis system gives me a headache when building 2-Axis Type turrets. They tend to be huge, and if they look good, they stop rotating on one axis (because blocks, well, block them on one of the sides).
The coulour scheme makes it look plastic, 100% with you on that. Honestly, I didn't think much on it ealier. Though, all gray ships don't look to good either. Maybe I will experiment with camo patterns, like navy ones, blue-white-gray stripes? Going to check it out.
As for the weapons: with RJam on it was enough to deal with the Isanth's. Took a few minutes, but dealt with them. That's something ;)
PS. I have a lighter prototype (almost twice lighter!), something close to a flying wing (which is not helpful in space, duh). It's a bit weaker, but I could put almost all I wanted to have in it. I could refit it to be an AI drone.