6105’s are a huge step up from the 6095’s. As such, an upgrade to a couple 6105’s would make a huge difference as would adding one to your existing mix. Now 2 6095’s vs 1 6105 would be a tough call. The 6105 has a wider flow pattern and having it at one end of the tank pushing down the length of it would create a very nice current across the tank. Especially if you spend the time getting the on/off intervals dialed in well for your display to get a decent back and forth surge. With 2 6095’s, they would likely be best setup at opposite sends of the tank in an anti sync pattern meaning one is off while the other is on and each running for a very short burst. The issue is that the 6095 won’t generate as much flow at the opposite end of a 66” wide tank where the 6105 will. If it were me, I’d be running 6105’s. The stream 3 would be interesting but I still think I go with 6105’s over the Stream 3.