Ya there are some people that keep it really simple and have it setup exactly like you mentioned, a nice big rock a turtle dock or a dock on each end and a filter for the water. And they will put a small real pant in a pot or a fake one on the island for cover. If doing it this way I like fake plants for fish tanks because instead of taking up the room on the dock a lot of fish plants have that weighted base to keep them submerged, so you can place the plant in the water and it can come through the back or over the side and let it kind of drape over the dock.