I finally opted to get rid of the 0-27 curves on my inner loop and go to 0-31. Haven't really run any trains on it except some test runs/clearance check runs but I'm happy to have another loop to run my big engines - 4-6-4s, 2-8-8-2s, 2-8-2s, ES44, etc. Previously they were limited to the outside 0-42 loop while my smaller locos stuck to my inner and upper loops. The upper loop is still 0-27 and I have no intention to change that.
I may purchase another Ross switch (anyone want a "parts" switch? Check the For Sale forum shortly!) for another siding. Will have to see what I can do downstairs. I like a lot of action but have felt rather "bored" with the current layout but don't want to expand considering a move in the next few years is going to happen. May put up a "suggestion for improvement" post in the future.