You have 6 sq. metres of run space, so at 2 sq. metres per LF hybrid you would be OK with 3. Garden hybrids do vary quite a bit in size so it might be best to choose fairly compact ones. Columbian Blacktails are very nice birds, lots of character, quite small and elegant, golden brown with cocky little black tails, and they lay very large eggs for their size. Alternatively, not a hybrid but if you can get genuine Cream Legbars from a good blue-egglaying source they are ever such pretty, small birds and mine lays as well as my hybrids, now well into her second year. There are also lots of hybrid breeds which are actually bred to be calm in more crowded commercial conditions, so they are friendly and gentle birds, such as my Amber Star and Silver Star. Some hybrids lay like mad but can be flighty, like the White Star leghorn crosses, so less suitable for an enclosed run. Speckledies, Black Rocks and similar such as Bovans Nera, Black Star etc have been bred specifically for organic free range use so are best kept where they have more range and space. Also Speckledies are quite large birds. Whatever you get, do enquire closely from the breeder about their probable laying performance. Most of the commercial hybrids will lay well, but if you buy them a generation or so down the line from a private breeder who has been using his own stock, not consistently chosen for egglaying and hardiness, you may end up with something less satisfactory. On the other hand of course, if you get a hybrid that gives you a satisfactory number of eggs per year (200+) she may well go on longer than one bred to go mad laying 300+ in the first two years and then succumb to prolapse etc.
Most of the breeds with pompons, fluffy bits or other special features will have been bred that way for showing - just as with dogs, breeders tend to exaggerate some features at the expense of other more useful characteristics. Personally I think that, in both chickens and dogs, there is more beauty in a less showy breed, hardy and in good health, with glossy plumage or coat, enjoying life in good conditions. Whatever you get they will soon impose their own individual personalities, but you might as well have lots of lovely eggs as well, after all that hard work!