All quail are generally 'flighty' if untamed, however the extent of which will differ between species. Yes, they are ground-dwellers so they'll spend the majority of their lives running around on the ground being quails. Generally when quail feel threatened, they'll make a dash for a hiding place as they are very nimble on their feet, so make sure to provide a hiding place or two in-case they need to run away from the birds at the top of the aviary.
Button quail/King Quail/Chinese Painted Quail are normally the best type of quail for aviaries \as they will more than willing to pick up any spilled seeds and are normally able to live off seeds, although it would be better for them to have additional protein supplements such as meal worms, kale, scrambled eggs, etc. and of course the usual shell grit.
They will only fly when spooked, and this is otherwise known as 'bonking' because they fly straight up into the air very quickly and won't be able to tell whether there is a roof or not, which results in a 'bonk' on the head. This doesn't happen often and it shouldn't be a problem for you because your aviary seems very tall (I have no idea how to use the imperial system).