It all depends on what kind of riding you want to do, and how much money you want to spend.
V8's/V12's are a good compromise. Certainly not the grippiest or lightest, but more than adequate and good value for money.
I personally don't like the thickness of them, and currently run Hope F20s. They are expensive, but they do last, however unless you know you want to use flat pedals more, I wouldn't advise spending that much money on pedals.
Shoe wise, anything with a reasonably flat softish sole should good, however flat pedal pins can destroy soles very quickly, so it's a case of compromising between not too soft that the pins tear the sole apart, and not too hard that the pins don't grip very well.
Classic cheaper recommendation are waffle sole Van's, which you used to be able to pick up relatively cheaply on offer, however it's not something I personally use.
FiveTen's are the best, however you pay for that performance, and most of them are like sponges so not ideal for wet winter rides!
I've tried numerous shoes over the years, but FiveTen's just work. Your feet stick, they don't get bounced of in the rough stuff, and the soles last well. I can generally get well over a years use out a pair, and that's covering over a 1000 miles in pretty steep terrain.
I have however just got some RideConcept's TNTs, and I'm quite liking them. I do find my feet floating about on the pedals a bit when climbing for some reason, but on descents they're fine. Certainly far better than the Ion Teflon soled things I have as back up pair, that I bought because FiveTens were proving hard to find (I thankfully got a new pair in Les Deux Alpes this year, which highlighted just how rubbish the Ion's are!)
Plus today proved they're not as sponge like as what they look, as I managed to stall while crossing a stream and soak both feet over the ankles, yet they weren't noticeably wet by the time I finished, whereas FiveTen's would of been like a couple wet sponges, and take days to dry out.
Given you normally ride clipless, if you're getting flats to work on technique, I'd highly recommend some shin pads, or at least thick trousers/long socks, until you're confident about keeping your feet on the pedals. Getting a pedal in the shin or calf, hurts. Generally eye watering, and not wanting to look kind of hurt!
It can lead to some brilliant scars though :-)
