MaxQ hit the nail on the head...
First and foremost - A well done website with sdetailed information about the contest, online registering and payment, and a list of registered teams.
A site map with ability to choose your site at registration.
Reliable 30A electric
Available Ice
Water
Good Judges
AND a cool well lighted place for them to judge.
Efficient check in
Efficient awards ceremony
Unique GC and RGC trophies are cool.
Ribbons for the rest.
Cash prizes given out at the time of awards
Clean "facilities"
Having trash pickup is nice too...
I don't really care about t-shirts, bags, pins, or other contest swag... if its included great, but save your $$ and give that cash as awards or to a charity etc.
Same goes for meals etc... I'm all for a free meal, but honestly most of us can cook a bit, or make a sandwich and call it good. Save that $ for prizes or charity... especially in a first year contest... If a restaurant etc wants to donate meals... well by all means go for it.
People's choice... this is a tough one... I know that this can be a big money maker for the contest, and I want to support the contests/charities, but most cooks view it as a pain and don't participate. If you can figure out a way to do that and not have it be a big burden on the teams... I think Enid does a pretty good job, they load you up with ribs on Friday at arrival and PC is Friday night so no "extra dutys" on Sat AM. Stillwater also does a "low impact" event by basically taking all your leftovers as "donations" which they then sell by the pound to the public on Saturday.
That's all for now... I'm sure I'll think of more later...