Talking about missing buffers..... apologies if you are already aware of this..... but the buffer beams are not straight and they should be. A replacement beam with cast buffers sorts that out. As far as detailing goes.... how far do you want to go? Replacing handrails with 0.3 wire. Lowering the AC units. Reducing the gangway length. The gangway doors could do with some attention. Replacement bogies (Replica). Shawplan windows. Plenty to keep you out of mischief.
Griff