Now, this is my two cents from the standpoint of using a handgun for self defense only. The three gun sounds like fun, but I don't have enough time and focus on self-defense and if you are interested in self training on the pistol, consider shooting around a barricade.
Put a barricade up and try it again from 5-7 yards! ! ! That really went a long way in helping my skill and techniques.
I have found that I needed to have multiple techniques in the trick bag to choose from.
If all is open I like the light on my left temple (right handed) with an unsupported single hand gun hold. Yeah, yeah I know the light is by my head as a target but holding up and over is awkward and slow. I prefer and think it is superior to hold the light on the side of your head. If you, for instance, hear a sound and turn your head to ascertain a threat location holding the light in your hand takes significantly longer to get the light "on target" then having it held against your head. I want to see the threat as quickly as possible to dazzle and address the threat...my 2 cents...for me I think a threat that has tipped his location off has a lot more time to see and shoot me if I don't know where he is when that light is up in the air trying to keep up with where my hearing has already told my head and eyes to look...try it both ways and let us know what you think.
I search from top then down and then more detailed top to down and over and top to down again, etc.. I want to see a threat (face and hands) before I illuminate his feet.
I do not like my strobes...they "freeze" the user somewhat too....especially when there is a lot of reflected light. And I absolutely hate the buttons that change modes...it sucks to want to illuminate and get the SOS, strobe or low power function...no kiddin', sucks, slows you down and throws you off...not what you want to do to win the fight. Think about it. I am only buying lights that change modes by twisting the bezel from now on.
I think you can have too much light in a house....for me 200 lumens seems right. More tends to "dazzle" me too. Outside more is better unless you have barrier to peer around. You can be behind another threat and illuminate yourself easily with a lot of light around a barrier plus dazzle yourself. If you are shooting 20-50 yards plus...go for all the lumens you want. However, I think that night shooting will be primarily at close range and/or indoors so I'm sticking with 200 lumens +/-.
If I am shooting on the right hand side I either use the crossed back of hand to back of hand method to get the light around the barrier on my right hand side or I hold the light over my head with my left arm over my right shoulder (awkward and does not provide support for the shooting hand).
If shooting on the left side, being right handed, it just sucks. I hold the light high over head with just enough light on the gun to see the sights and then lean over...it's not great, let me know what's better.
I do like tritium sights...but only because I have Trijicon HD with a flourescent orange front ring I can illuminate...the rear sight with tritium dots will improve my shooting accuracy at a cost in speed...without the HD I would black out my rear tritium sights like on my M&P 45 that does not have anything to easily distinguish the front sight. I like the Trijicon XD rear sight configuration with a wide slot...it really helps at night compared to the older model on my M&P.
Oh yeah, I move with the light off. Search and shoot with it on.
Just my 2 cents....your mileage will vary.
Try the barricade and let me know how that affected what you perceived and how you address your techniques afterwards.