Agreed trailing gear is a great befit on all, but the perfect landings, and how often do we do that? LOL but the OP did say he wanted to keep the thing simple, retracts, brakes ect all make the whole thing more complicated, it's possible to put retracts with trailing legs in and lock them down to keep the air system out of the installation avoiding its added complications, trying to find leaks ect, just an opinion to keep it simple and if after a little while the OP wish's to add retracts he only has to tube them up.

Mike