(1) Favorite dish/container for feeding regular foods/kitchen scraps to a small flock (we have 6)? I've been using a glass pie dish set up on bricks to keep the ants at bay and my girls walk in and across it and knock it off.
Personal preference: I like to use something that would otherwise be thrown away. Often I cut the bottom part off a plastic 1-gallon jug (like from milk) and use that like a bowl, but sometimes it's a container from cool whip or sour cream or hummus or lunchmeat or something like that. I rinse & reuse the container until one day I decide it's too dirty, and then I throw it out and start using another one.
The container sits on the kitchen counter, and each day I go dump it on the ground in the chicken pen. They don't mind eating off the ground, and anything they don't eat gets mixed into the bedding to compost eventually. If I have a bunch of extra-wet scraps, I sit the whole container in the chicken pen for them to eat, but that container doesn't go back to the kitchen counter-- it gets thrown out when they're done. If I have a long stretch with extra-wet scraps, there will be one container on the kitchen counter and one in the chicken pen, and I dump the scraps from the kitchen container into the chicken one each day.
A lightweight plastic container does not stay in one place, so I have to go retrieve it from whatever corner the chickens have tossed it into. That's part of why I usually dump out the scraps, because I know the chickens will dump them soon anyway, and this saves having to pick up the container later. Having the container move around is not a big deal for me, but I don't know whether it would matter to you.
(2) Are there any benefits to specific feeding times? I usually take my girls scraps mid-day - lots of high water content foods with the crazy heat. But, wondering if I should switch to evenings. Chick feed is available all the time.
I think most times are fine, as long as the chickens are awake and have time to eat before bed.
I wouldn't want to put scraps out in the dark, because then mice or rats or something might eat them before the chickens got their chance. (I prefer to feed chickens, not rodents.)