Oak biodiversity is centered in North America, with somewhere over 300 species. In states like Tennessee and Kentucky you may have 20 different species of oaks. In Illinois we have more than 10 species. Obviously the Japanese never had access to try any of them for bonsai until only recently. So the range of possibilities is largely untested for bonsai. I would not limit my choices to only those species that have a track record as bonsai, as there has simply been relatively little effort to "test" the many different species.
So which ones to seek out for bonsai? All oaks have fairly coarse branching structure compared to an elm or hackberry (Celtis). So with pretty much all oaks, the best use would be for medium to larger size bonsai. Trunks are the most important feature of bonsai, the appearance of age to a trunk is largely due to texture of the bark. There is a wide range of bark textures in oaks, and the textures are not limited to one group or another.
Evergreen leaves are a feature that occurs in unrelated families of oaks, but in common name parlance, "Live Oak" refers to any evergreen oak. So the use of the term live oak can be misleading. Most of the California live oaks, Q. agrifolia for example, are in the red oak family, where the southern live oak, Q. virigniana is in the white oak family.
Red oak - black oak group of some 80 to 90 species only found in North America & Central America. They most commonly have a flat plate forming bark, like Quercus rubra, the northern red oak, or Q. velutina, the northern black oak. It becomes rough with age, but not very dramatic until advanced age. There are some species with more coarse bark, there are some like the cherry bark oak, Q. pagoda, that have smooth bark almost like a young cherry tree. Some species of the red oak group have smaller leaves, for example the willow oak, Quercus phellos, water oak, Q. nigra, and myrtle oak, Q. myrtifolia. Others, such as black oak, Q. velutina have pretty large leaves.
The White oak group includes the white oak, Q. alba, swamp white oak, Q. bicolor, and the bur oak, Q. macrocarpa, The group is spread through the northern hemisphere, so it includes the English oak Q. robur, but does not include the cork oak Q. suber. Most of the white oak group develop a fissured bark, often fractured into a pattern of squares. Bur oak has the most dramatic bark of the group, followed closely by the white oak and swamp white oak. Some have fairly smooth bark, but the majority have coarse, fissured bark.
So which to choose? I would get the best trunk you can find. Collected trees are the best in terms of collecting a trunk with bark that indicates age.
As a general rule, oaks from seed take considerably more time to develop than an Elm or Zelkova. As a general rule, they are medium to slow growing trees. It will take more than a decade for seedlings to begin to display mature bark patterns.
Leaf reduction, my limited experience seems to be that all the oaks I have tried, all the leaves will reduce a fair amount. You will probably be able to keep leaf size under 2 inches on a mature, well ramified tree. This includes bur oak. Many oaks, when in youthful vigor, will throw very large leaves, my bur oak had leaves 10 inches (25 cm) long. But the same bur oak "calmed down" to leaves about 2 inches (5 cm) long as ramification increased.
So check out what you can find of your local oak species. There are some unique ones out there. Local will be best adapted to your winters. Or seek out stock from further north (colder) areas, so that you can get away with putting little or no effort into wintering your oaks.
. Personally love Q. marilandica, stellata and arkansana.
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