I hatched a wide assortment about three weeks ago and came out with one lone bantam cockerel in the bunch. I'm wondering if he'll be able to hold his own against the full size cockerels as they mature, or will he probably get his feathery tail handed to him? Has anyone had success having bantam and LF roos living together? Do you think I should separate him when they start crowing and try to get him some ladies his own size?
I've always kept LFs with banties with no significant issues (one very large LF male hurt a tiny banty hen, eventually, but he was on the cull list anyway for his attitude; the rest of the LF males have been very conscientious).
They get along normally, though the banties generally get more respect overall than other LFs give one another. Banty males in my experience never have trouble mating LF hens, and vice versa, but some people have a lot of problems there; depends on your birds, so best to watch them somewhat closely. Observation on a regular basis will show many problems coming before they're serious problems; most social chicken problems that occur supposedly "out of the blue" from fatal attacks to serious diseases were not at all 'out of the blue', it's just that the person did not monitor their birds sufficiently.
Generally, banty males more than hold their own, as do banty females, it's not uncommon for farmyards of LFs to be ruled by banties, in fact it's quite possibly more common than the reverse; they're generally 'more chicken in a smaller package'. When I first got chickens my concern was that the banties would kill the LFs, lol, not the reverse!
Overall they are usually smarter and more instinctive and those are the traits all other poultry respect over size or strength in alphas; LFs in my experience, whatever the breed, prefer to reproduce with banties rather than their own kind.
Outright psychos and obsessive animals, i.e. the mentally unwell ones, can rise to alpha status simply because smarter, more mentally stable animals don't want to risk their lives in challenging them, but it's important not to confuse alpha position with alpha worth; some alphas are only alpha because they're effectively rabid in their interactions with others, not genetically/ physically/ mentally superior in any way; in fact their mentality is indicative of inferiority, it's often a massive overcompensation. Unfortunately many people think alphas only become alphas because they are superior, not bearing in mind that domestic chickens represent very 'interfered with' and unnatural aspects of their wild counterparts; we've bred in and out and altered all manner of important traits both physical and social.
Breed what you want to see, so if you have a violently intolerant rooster (or hen) and you like that, just be aware your whole flock is eventually going to end up predominantly as the animals you choose to keep and breed. If you have a male who will not tolerate a banty, his intolerant attitude will almost certainly be inherited as mentality is very strongly heritable, and if there are no banties to attack he will shift it onto something else, like hens; intolerant, vicious, bully birds will always find something to victimize. Too many people remove the socially stable birds, thinking they're only picked on because they're inferior as per the old 'law of the wild' they mistakenly believe applies without qualification to domestics, and keep the vicious ones, and then complain that chickens are so violent. Well, yeah, they are if you select for that trait, LOL! Unfortunately people breeding on such predispositions are many, and have effectively convinced the public that it's inevitable, it's 'just the way chooks are'. That's like someone who breeds fighter dogs convincing the public that all dogs are 'just that way'. Grossly incorrect.
Tolerance is partly genetic, and partly learned; if you separate your banty male now you will possibly never be able to reintroduce them. Right now, you've got the ideal setup 'starting pack' for a banty-tolerant flock. Chicks raised together sort out their hierarchy early and their post-puberty fights will be less aggressive as a result; only extremely violent individuals will cause harm to others they were raised with.
There is no male less male-tolerant than one raised separate from other males or kept separate around puberty; there's a large chance he doesn't understand how to concede a fight, and will keep trying when it's apparent (to everyone else, anyway, not necessarily to him) that he's going to die if he won't submit.
Chooks have submissive and threatening body languages, behaviors, and vocalizations; it's important to allow them the ability to experience socialization or, like unsocialized dogs, or any other naturally social species kept in isolation, they become dangerous and are socially ignorant, and will turn what could be a mild scuffle into a fatal fight.
Best wishes.