1) it's actually extremely easy to do this with world guard you just need to define the regions, which really isn't much work at all just some flying or teleporting around and repeating the same command to define its boundaries. you create one main region and in your case 3 inner regions then set the 3 inner regions parent to the main region and it eliminates the hassle of having to set everything up for each region as the child regions adopt the rules of the parent, then you'd just switch the welcome messages for the 3 inner regions. I'm sure our lovely admins already know about it but here's the command for reference
setting a parent region2) again extremely easy to do, but ima have to agree with claw, it's very unlikely. mostly because i doubt the admins want warp signs scattered all over the world at various builds but hey it's up to them whether or not they're willing to do it.
3)here's a list of
all the flags im sure you can use common sense to filter out which ones they probably wont allow, but it doesn't hurt to ask about a specific one
4) can't say definitively cuz it's not my call, but it's been my experience that there's a large trust issue with allowing people to build in protected regions such as these, not to mention the argument of whether or not you'll be using your own materials or be given stuff since it's technically a server build not a player build... it just gets iffy. pretty much if the admins think they can trust you they "may" let you do it, wait for them to respond.
pretty much all of these things are possible to do in a relatively easy manner, the real underlying question is if one of the admins is willing to do it for you given they're the only ones capable of doing so.
your best bet is to just ask nick. i'd say ask tobs but he'll prolly just ask nick anyway cuz well seniority....
