This ship is very original, and that's why I like it. The whole idea of the large, open superstructure for repairing or constructing spaceships is very practical, and the way you portrayed it doesn't disppapoint. The ship also has a harmonic appearance, each of the parts goes well with the others, and this gives the ship a very complete appeareance. A truly amazing job.
I sent you a message through the devianart message system. We are interested in using you for a project. Would you be interested in exploring our project? Would you have time to discuss on skype? Please message me with your skype details and we can figure out a time that works. Or you can use my email sent to you in the message. We look forward to the opportunity to talk with you.
I hear you mentioned it was a repair dock for medium ships, but I was wondering - it may even sound obvious - but it would be a great platform for fighter/bomber fast repair and resupply. It's like having the good old 5T truck on your back refreshing and resupplying the troops on the fly.
I realize this is an engineering vessel, not a war machine, but if you were to equip some defensive armament, might I suggest a mass driver? You could run it the length of the vessel, allowing it to accelerate projectiles to enormous speeds (you could probably even use the tractor beam to do it, if specially applied). The only problem with this scheme is that the ship could only hit something directly in front of it, which might call for some maneuverable steering or additional weapons (of course, this isn't a warship, so one weapon might be enough in this case).