Well, I already made a post about this in the Design section. You can link to it here;
/8/5a/92528/1.html#post926828
But this thread I wanted to designate for an actual suggestion. While I described before that there is currently no way to make a perfect sphere or surface of greater than 10m in any direction without using an excessive amount of prims and a heavy texture job, I also stated that I was wondering if Linden Labs was planning on creating arc components that can be made to allow an easier time to construct these features. The largest problem in these parts, is that to form an arc segment, one has to create a cylinder or sphere of 10m in the desired 'longest' direction, and cut it into being a 5m long piece. That is the MAXIMUM dimension possible for an arc segment with a flat end.
The second problem is that we have no way of shaping the flat end to be of any angle besides where it is cut by the radius of curvature. This leaves shaping the inside of the sphere, as well as trying to create any sort of line or addition to enlongen the arc artificially, a mess. Of course, it goes to help serve as a guideline, but if the boundry has to be transcended to complete the desired design, one is stuck.
I know that if new pieces had to be made, then they would have to fit into a 10x10x10 measure. If it would be possible to make an arc-menu or something of the sorts in the items box, or add in two new items (one for an arc, and one for a cylindrical or spherical arc) then that would definitly help with the problem. That is, the arcs would have to have a customizable thickness that is independant of the axis of width or length. Of course, there are tons more that can be done or arranged to be done with the hollow command, but I'm too out of it due to these confounded painkillers to make much more sense. So.. get back to me when you can. And thankems.
PS: I know that adding 2 items to the server database would decrease server stability due to those prims having to be added and idealized to every sim, but I am not sure by how much, or if that is a considerable factor..