I don't really like the big rotation point for each barrel on the turret. It doesn't quite look like the correct, or logical way to do that. Is there any evidence of a similar turret mechanism in real-world examples?
Otherwise your chassis detailing does look nice.
S44 and Operation Polaris have shown that tanks can look very nice up close with little greebles, so don't be afraid to add little boxes, bars and other nurnies (unless it's against what you're trying to achieve artistically).
sexy S44 tank
another Note how the modelled cylinders and vents work a lot better then simply texturing them on, because of the depth they give to the model
Operation Polaris model
w/textures
Obviously these are based on real-life things, while yours is sci-fi, but the best sci-fi gives a clear nod to realistic precedents, so it could be an interesting way to 'detail' your model, especially seeing as this is a bulky level 2 unit.
Of course, I can respect an artistic decision to keep it plain, but my personal leaning is to detail it a little bit more.