For home defense a light is important for identifying your target. I elect to use an RMR on my nightstand gun but I do practice and typically shoot dot guns, like the others mentioned you might be better suited with a good weapon mounted light and a good set of irons. The Swampfox (Liberty or Justice), and Romeo 1 Pro are nice since they have a shake wake activation. I have an RXS 250 I'm probably going to replace the RMR with when I swap out the batteries as it's top loader.
Going with a dot will require you to change the batteries and also with a weapon mounted light ensure the intensity of the dot will not wash out with the light. Do you typically shoot glocks with red dots? If not you're better off with a weapon mounted light and iron sights.