Hi Again
A rooster will not make the hens go broody and there is noticeable difference between a fertile egg and an infertile one, so the only reason not to have a rooster is "the law in your area", the noise(although some chickens can easily make as much noise but not at the unsocial hours that roosters sometimes do) and the extra mouth to feed. I have roosters run with my egg production hens and in fact I keep all my chickens together, broodies, chicks, adolescents, point of lay and layers and cockerels. It's much easier to my mind, than keeping them separate or trying to reintegrate them later.
The red sex links should be fine but, unfortunately, you have other breeds there which are also prone to broodiness and people often find that once one hen goes broody, others follow suit, so you will most likely need to steel yourself and "break the broodiness" sooner or later. Some hens will raise 3 clutches of chicks each year, so indulging their maternal instinct especially for someone else's gain, could become a very expensive business... I had 14 chicks in my first brood, 8 in my second and 9 in my third.....so I am speaking from experience here, although so far I have kept them! I started the year with a trio. I now have over 40 chickens of varying ages and breeds..... it's very easy to become overrun!
Yes, 8 eggs is about right for a clutch. My first broody accumulated 14 of her own eggs in a secret nest and hatched all 14 and she is quite a small hen, but I have restricted them to 10 or less since then. I got 8/9 and 9/10 but it depends on the fertility of the cockerel and how many hens he runs with and how good the broody is as to the percentage hatch.
What are your plans for your red sex links when their productivity diminishes? Presumably, if they are pets you will keep them but if you have regular egg orders, you will need to replace their productivity in which case, it might be nice to have some home reared pullets coming through, but then of you are already at housing capacity, you would need to do some additional construction. Lots of things to consider. There is more to this chicken keeping lark than at first meets the eye! In fact some quite serious moral dilemmas!
Good luck with them.
Barbara