To answer about cashing out, I think basically you're looking at two options, mostly based on the relationship with your players. I play with some friends, we very often only play 5-6 handed, on occasion we get 8-9. These are all some of our best friends, or parents of our kids' friends, that sort of thing. Especially with some inexperienced or low-expendable income buddies, .05/.10 is the choice for majority of games.
Option 1 - Venmo. Besides exact change, it also allows for more impromptu games. We decide last minute to play some microstakes, everyone venmo so and so and cash out later. Drawbacks: psychologically frustrating as banker at times, it's really easy to just keep adding on since you are not paying anyone else, and it's a bit deflating to see the venmo account disappear during cash out (even if you are up). It's also really easy to lose track, someone says "hey I'm adding on $20" you grab them chips, you both get distracted by a hand and forget. Especially when drinking is involved.
Option 2 - cash, and just round down. Keep the change as sort of service as banker/host, and just make it clear you're doing it this way. Still probably need a lot of singles, though.
Our game has evolved a lot. Used to be little $5 winner take all tourneys, I was the only experienced player and everyone was comfortable with small amounts until they learned more. Our core group has moved up to .25/.50 match the stack, it can play pretty big. .25/.25 will be for expanded games, it makes auditing and final payouts more straightforward than the nickels and dimes.