My father owns and frequently uses these types of lasers on his self defense and target shooting handguns, and since I got into lasers he's always asked me if I could do two things: one, burn the ass hairs off the neighbor's dog from across the street (dog annoys him all day with barking, and the owners actually encourage the dog to bark after he asked them to keep her quiet), and two, make him a laser that is strong enough to be seen in broad daylight at a good distance. The best thing that I could come up with due to all of the constraints with space available, stability, consistency, and reliability is to house the module for a more powerful 532nm somewhere lower (i.e. below the trigger guard where there's more room) and run a fiber-optic cable to direct the beam where you want it. Sure there will be some loss from the cable, but if you get a DX 200mW green module (probably somewhere 110mw~150mW in reality), even with a 50% loss of power you'd still get ~60mW of 532nm, which is easily visible from a good distance even in broad daylight. Another option would be to extend the available space sideways, but then you'd lose ambidextrous capability. My Dad's leftie so I could do either as a one-off for him (if I ever get confident enough in my laser-building skills to actually do this), but that's what I've thought of so far in regards to gun lasers.