If an individual is involved in more than a couple aspects of the hobby, is there a point of diminishing returns? IOW, I guess the thing that really sticks out in my mind is how to devote the time necessary to address all the maintenance related issues that come about when involved with several endeavors within the hobby and is there a point at which one finds it is no longer fun...

When you leave one aspect to take on another, you forget what's going on with the one you left momentarily or do you? Thinking a dry-erase board listing all your aircraft with columns used to keep abreast of status and issues needing attention as would be found in say a business type environment might be required. Anyone do something like this?