On the subject of redirects, I don't like a doubled rope running through either type of gate. Redirects are more a technique of work climbers. For a rec climber it makes more sense to simply double crotch with the other end of your rope rather than redirect. The advantage being that you don't have to climb up to take it out like you do with a redirect. It takes a little longer to set up a double crotch (not much longer)but you eliminate the problem of rope running though a biner. It's also much easier to come back to the tree from an outer branch tie-in on a double crotch than it is on a redirect.

Rec climbers can learn a lot by paying attention to how pro arborists climb but there's a point where some work climber technique makes less sense for rec climbers. Secured footlock ascent is a good example, makes no sense for rec climbing. Cool skill to master but otherwise not useful for rec climbing.
-moss