As far as the wooden board circle, if the circle does not fit on a single continuous surface, the breaks caused by multiple boards would weaken the effectiveness of the spell or drastically increase chance of failure. My personal answer is to have the boards carved so the full circle could be filled with something else, such as salt, wine, mud, sand, etc. The filling material is the actual circle, which could allow for the multiple circles based on the spell list. As far as RR to cross a circle, I look at it as the circle is containing or protecting against the planar energy of the target, i.e. I would require a resistance roll to cross the circle used to summon a ghost/spirit from the same plane as the caster, whereas summoning something from the elemental plane of fire would only cause an RR for those allied with that plane (see Elemental Companion).
As far as the hoop skirt idea, this would be useful for assorted circles associated with the multiple hoops in the skirt. Using it for summoning, however, should be at best problematic. Do you want to summon a minor demon into your skivies? To see a good example how a wire hoop can be used to assist in multiple summonings, check out what Binder did with the wire hula hoop in Skin Games, the latest Dresden Files novel.