View attachment 1617670
View attachment 1617671 Definitely keep the mean roo separated from everyone and get him rehomed asap. It's possible that your hens have already had enough "seeing" each other to be put in together and get along fine, just a little pecking order settlement. This article will let you know how introducing separate flocks should go:
See But Don’t Touch
Usually 2 hens is not enough for 1 rooster... even 4 may not be either, you'll just have to see how it goes. You might have to end up getting more girls to keep everything peaceful. Otherwise, your space and your setup may only be conducive to raising a few hens only. Here's an entertaining article about roosters:
Keeping A Rooster
Best wishes with your flock!