The word "Unable" is seldom used by PPL for fear of being denied a clearance (in this instance no clearance is necessary anyway). Remember, the MATZ is not controlled airspace and therefore you can be 'firmer' with your response and state that you will be maintaining X altitude or Y height and whilst we all want to be helpful THEY CANNOT INSIST you obey their instructions. You must, however, respect the ATZ which is usually 2.5miles away from the centre of the longest runway. Perhaps a sharper controller would have vectored you away from the main runway/circuit to enable more 'vertical distance' between you and the ground.
Very well put.
Low hours, if it never came up too much in training, it is understandable for PPLs to be shy and not firm enough.
Unable, and state a minimum height/altitude you are able to maintain, if they are unable to accommodate your transit then route around, hold, or if you're feeling particularly brash then continue as you don't technically need clearance to do so (but be prepared for a heated phone call once on the ground).