I’ve done some searching on footwear and it seems that a lot of styles that have been suggested are no longer made, or are soon to be that way (e.g. Keen Bryce and Teva Links). FiveTen is popular, but some say certain models are too heavy/bulky…or the soles have too much grip (depending on your type of riding). Some Sketchers and Vans look interesting…
Any suggestions?
No such thing as too much grip IMO.
I use 510 Impacts and have said before that they are the single greatest purchase I’ve made towards my unicycling. They will change how you ride. If you stick to any of the stealth soles (Puma thing with all the little circles on the bottom) you should be fine.
I rode with tennis shoes for a long time because I didn’t believe shoes were important, however I’ve found that they are far more important than what pedal you choose (with the right shoe, you can ride nearly any pedal).
MTB specific shoes have a stiffer sole than Sketchers and Vans. I’d stick to those.
Mostly depends on what type of riding you are doing. So… What type of riding are you doing? 
I won’t say the purchase of the 510’s were the single greatest item, but they’re right up there in the top 10. That being said, I wish that 510 offered a lighter version.
+1
OK, + a LOT.
My 510 impacts changed my riding overnight. Literally. I was in the learning stages several months in and was having a heck of a time riding anything but smooth and straight. Once I bought the impacts, I could suddenly do more than just push down on a pedal. Turning became easy. Control on singletrack appeared.
It was amazing how much control (and therefore confidence) they gave me. I’ll never turn back.
I can’t speak for the 510’s as I don’t own any, but stiff-soled, high-grip shoes are what you want for MUni and distance riding. Don’t be afraid of ‘too much grip’, there are even people on these forums who love clipless setups because the extra control you get is beyond anything else.
I personally wear safety boots (I’ve had a couple different types) and can’t speak highly enough of them, BUT the caveat is that they weigh a tonne, specially if you get a pair with steel toecap/soles. The advantage is (If you buy the right pair) they’ll last you a super long time (They’re made to withstand construction sites) and they look like normal shoes, so you can easily unicycle to a job interview and not have to sneakily change your footwear before you go in. Get a pair with a proper rubber sole, not a plasticky one too, far more grippy. The other obvious advantage is that if you UPD badly, your feet remain intact 
Another disadvantage is that they tend to have quite high ankle support, which can restrict movement. If this is the case, break 'em in a bit and don’t tie them all the way up (The obvious way to avoid this is to not buy boots that go that far up!)
I bought some fiveten impacts and I would definitely recommend them. I mostly use them for commuting on a 36". The grip they have is impressive, but I don’t think it’s too much.
Before I bought those I used DC skate shoes, but the tread seemed to wear out pretty fast and eventually created holes in the bottom.:o
510 Impact lows. I wanted to buy a mid or high-top, but the store didn’t have that. However, the low-top has a ton of padding next to the ankle bone, and that keeps the ankle from being bashed in most situations. Before the 5-10s, I used skate shoes, and the arches of my feet were sore after riding. Yes, the 5-10s are bricks, but UPDing on a hard surface feels really good. I tend to hug the cranks with the sides of my feet, frequently causing a loud squeaking sound. I’m going to have to experiment with applying something to the sides of the shoes and/or the cranks…to deal with the excess friction. I’ve owned the 5-10s for 4-5 months, and they are showing some trauma in discrete spots, but I think they’ll be lasting for a much longer time. 5-10s are an incredibly well-made shoe for the price. A bit of advice: don’t expect to like 5-10s for the first day/week/month. They take getting used to. Adjusting the feet on pinned pedals becomes a skill in and of itself.
Amazon dot com has some 5 10 shoes at great prices. I picked up a pair of Impact Karvers for $49 (reg $140) and they had my size. I notice the price discounts change all the time on there though. Shipped from and sold by 5 10.
If you’re riding street there can definitely be too much grip. Doing crank flips is way harder when your feet stick to the pedals.
Purchase
Well… after a bunch of research… I pulled trigger on some Five Ten Impact Lows.
I wanted to relay my experience with Bikeshoes.com and my dealings with Rob. Quick return emails and great customer service. They have a “price match guarantee” which he promptly honored. Free 2 day shipping on shoes… I think, too, that if you order before Christmas they’ll pay for return shipping if you don’t like the shoes.
Any way, there was no risk on my part (I have a hard time buying shoes through the mail)…and I appreciated the experience. I know he’ll take care of you guys/gals as well.