Maart3n is right about the stretching, there's plenty of pieces you can use to make the neck look better without stretching anything. The repetition...I can see why you used it on the neck, but otherwise, as I said, plenty new sections around.
I *do* have to point out that most Klingon ships *are* green and red in the first place.
The shape is decent, but you've been too easy on yourself. Experiment a little more, maybe check out the 'good (fan)shipbuilding guide' (in the useful links thread), use the many new custom sections to your advantage. Get rid of the holes, the stretching and maybe look at the K'tinga's color palette again, because contrary to most other Klingon ships their cruisers are a very light grey with washed out red-ish details, as you can see here
Next stop, the weapons. A K'tinga's main feature is the forward torpedo launcher. It's just not there on your version. Agreed, ST weapons placement is finicky, but at least get that right.
That's about all I can say. Good luck.