With proper exposure & w/a little judicious noise reduction (I use Noise Ninja but Neat Image, etc. are fine, too), I think the M8's ISO 1250 performance is actually very respectable. If you're going to skip film RFs & go straight to the M8, I would suggest going w/the classic available light RF thing & just get a single fast lens, either the 35/1.4 Summilux, 28/2 Summicron, or CV 28/1.9 Ultron, & skip the flash unit entirely.
As far as bags, I will repeat for the umpteenth time my standard advice of staying away from actual "camera" bags & just buying any regular old messenger bag, briefcase, "manbag," etc., that you find comfortable using & then getting a camera equipment insert from Domke, Tenba, Billingham etc. that will fit inside your chosen bag.
I don't know why you would want a black finish camera or need a "Thumbs up" grip, but that's a personal thing. 😉