Any luck with led lights for the rail that don’t protrude past the end?
I have this combo on my M&P9 compact, but it fits the M&P22 compact OK, as well.
[ame]https://www.amazon.com/HiLight-P3GL-Strobe-Flashlight-Rechargeable/dp/B01N76T3J5[/ame]
Green laser above the light, so the difference in height with the barrel isn't as much as most that have laser below the light.
Quality isn't the best, battery is a little small, it's not a quick release attachment, and I'm not sure if it's made in the USA, but it's only $60, fits compacts and some subcompact rails, and it doesn't seem to loosen up after a short trip to the range.
For the safety plugs, I don't think the ones for M&P9 fit. I just took apart my M&P22c to check and almost lost a spring

I suppose you could use a dremmel and cut off the paddles, or pliers and bend the paddles out of the way of your thumb. But I'm not sure where you can buy a replacement safety in case you want to restore it to factory appearance, or accidentally destroy it.
For sights, I got fiber ones from Williams Sights. Rear for compact is only elevation adjustable, though. I chose it because I preferred the green front and red rear. I think the other brands had the colors reversed. Can't find any night sights for this, though.
Williams Gun Sight Target Pistol Sights S&W M&P Compact .22LR | $4.96 Off 5 Star Rating w/ Free S&H