I have a GS8e (equivalent to 816e). I started out with mediums, then went to bluegrass strings. Then I purchased two sets of Martin Lifespan SP phosphor/bronze 13-54(lights). When I didn't like them on my Grand Auditorium (GA7), I decided to try the second set on my GS8e. The Lifespan P/B's are the only string I use now on the GS8e. They have the balance and brightness I like. There is no loss of bass. In fact, the only thing I notice is a little less volume. When plugged in, that's easy to fix, and around the house, my wife likes a slightly quieter guitar. Actually, when I use a pick, it is plenty loud. I suggest giving them a try.
Greg