Full on AWESOME steam plant you've put together there Mate!
I too love the twin stacks and the steam plumes they pour forth!!
You've really "tarted" that PMR #7 Twin up to perfection!!!
Only thing I'd do more would be to insulate your main steam line from the boiler to the oiler. Probably just use split neoprene tubing of the right size, rather than trying to wrap lagging cord around the whole length, that way it would remain flexible for use with other set-ups.