Normally i dont replay to the ban appeals, especially since we are not supposed to, but given the nature of the reason you got banned i was compelled to say a few things.
For starters You can buy extra plots for your town if needed, also i think joining a nation will give you a few more plots. if your worried about getting griefed or raided, griefing is ban-able here no matter what you grief, protected or not, so you cans till expand but keep your important things in the protected area. and of course raiding implies usually a grief in order to raid so..
Another thing you can do is get creative with the layout of the claimed chunks. a ciricle of claimed chunks around unclaimed chunks still protects them if you build walls, since no one can grief the protected outer walls to get inside.
For example, # = Unclaimed chunk
@ = Claimed chunk
##@@@###
#@###@##
@#####@#
@#####@#
#@###@##
##@@@##
Experiment with it and see what works best for you, Because there's no reason to cheat here in order to protect your area. The rules are heat to protect the economy and us, while alloting us to have fun, dont look at the rules as "man i wanted to do this but i cant" look at it as a challenge, "ok Hmm, whats another way i can do this. that works just as well but doesn't get be in trouble?"
Im not a staff member and i dont pretend to be, so if you doubt anything i say ask a mod or admin etc. I hope "IF" you are un-banned you will of learned from this experience and continue to enjoy playing with us. while now understanding that the rules can be fallowed while still getting what you want.