I strongly disagree that your small flock will be "just fine" out free-ranging. Especially without a rooster, lgd, etc. to help watch over them, winter coming soon and no tree canopies to help hide them, & wild prey growing increasingly scarce. Your flock MAY get lucky and be just fine, i.e. undiscovered. Sometimes people go years before experiencing their first predator attack; sometimes it can happen the very first day/night. You may be aware of the countless never-ending threads on this forum from heartbroken people who have lost flock members and sometimes their entire flocks to savvy predators.
I have 3 large flocks that range daily through woods and pastures. Losses have been relatively few due to guardian dogs that protect during the day, & fort knox coops at night. But despite mine and dog's best defenses, hawks, roaming dogs and fox have ocassionally been sucessful, always during the daytime while flocks were ranging free. Ive never lost my favorites which would leave me heartbroken, but All losses left me sad.
Its up to you to decide how much risk you are willing to take. Ive made Immediate adjustments after past sucessful predator attacks, including more fencing, more guard dogs, & locking hens up for several weeks until the lgds Finally suceeded in removing the evasive sly fox. My flocks still free-range daily, but i am fully aware of the daily risks. If you decide to let your girls happily roam free (& they will be happy!), just be willing to accept the consequences if they are "discovered." Wishing you the best.