I had people helping me before and honestly it is easier to do alone, with kids who were happy to get clear instructions with not so much free time to roam around and think of doing something evil They like doing things together as one group. The final dancing is the best, I have kids asking me if they can come visit again for some more dancing, hahahah.
I am used to having fun with kids and organizing them. The kids I had here a few times were 2-7yr old (I invite neighbors as well). At some point we were all singing English, French and some weirdly pronounced Czech songs. I did a bunch of bday parties, ice cream party, game playing party and we cook together with kids, about twice a month. I never had any catastrophy happening, just the little ones need to be looked after more, but boy, they make the best dancers!
It was great to do the craft (painting was another party, one arts and craft moment is enough honestly), since kids were motivated to do all that together, at one table. I had 9 kids the most, they all squeezed side by side, and copied and helped eachother. They are used to transfer to and from activities from school and creche, but this time, knowing cake will come, and doing all in a place with balloons all over and decorations, they were motivated and happy. They couldn't really wait for more instructions, it is always fun. I wouldn't have thought they would be so excited at our home since there are too many McDo parties around, Zoo parties, Museum parties etc., but always had a great feedback from parents.
The baking time is a nice change, too.
One does not need much organization during the actual party, as long as you get stuff prepared.
Dough I make an evening before and it only needs to be rolled out - 3 pins kids shared, (once when we cooked at home with a bunch of kids we made scones, kids ate with cream and jam, that was nice, too, it was fast, once we made little individual pizzas, once I cut out hot dogs and we rolled puffy pastry around and sprinkled cheese and herbs on top, that was a hit, too).
Masks just needed to be painted on and threaded, cake and finger food got eaten within 15 minutes. While we were singing and they played also a bit in between.
So, maybe it is my work that helps (I feel a bit odd sometimes for having as much fun as the kids), but the only thing that one should watch out when you organize at home would be not so many kids if you aren't sure, and, plan your cell maybe beep at you to give you an idea of time slots. Having a small place actually helps, everyone is right in front of your eyes. Parents are happy, don't feel like leaving when they pick up kids..
Other ideas for crafts would be - air hardening clay sculpting (making little cups, bowls or animals or whatever they feel like, they get inspired by eachother), large wooden beads neck-less (watch out of little kids snorting beads), making your own postcards, paper doll/animals/pirate cut outs, etc. There is bunch of stuff online. I often do crafts with a lot older "kids". They like.