Great question and a great rationale. Two HITs a week you would probably see better results too, but seems like you have pretty modest goals and a common sense plan to get there.
Depending on where you live this list may not be very helpful!
Tree Climbing, you can never be too old!
Bicycle Riding (not my thing)
Volleyball (beach preferred)
Jungle Gyms! (I've got the maturity of a 12 y/o)