Hmmm, I wouldn't say on the beta board that we have a flood of missions, but what we do have is a steady trickle of around 5 new ones per week in the ratio of 2 non-addons vs 2 off the cuff addons vs 1 x island. For me, that's pretty good volumes.
The mixes swap about a bit, but frankly, the quality in there is a wholesome lot better than some dreadful stuff 'out there'.
In terms of addons vs mission ratios. I believe it's current proportions make sense. Even if you were charitable and said 50% of people do addons and 50% make missions (and swap roles but never at the same time), then it's logical that the 50 people making missions have ONE addon each to play with. Hence the percieved dilution.
Bis themselves did make an attempt to address this imbalance with their AddonsAtEase utility, where it was required to at least supply A mission, for a given addon. I think that largely contributed to the failure of that scheme. It was an added burden, senseless and impractical for what has turned out to be classes within classes within classes of enhanced addons using other people's models. Who really wants to test yet-another M16? Let alone make a mission for the damn awful thing.
On balance, even when you look at what appears to be endless models spewing out of the Czech site, my best guess would be that reality says there's a ratio of 10:1 missions 'out there'. we see addons glorified because yet another enthusiast wants a machine gun with pink snowflakes and has found out how to do it. When similar happens to 'yer basic' mission, it's a big yawn and is promptly forgotten and isn't glorified with a sexy picture. Basic hype.
Don't forget also that many addons are simply country-centric. Play mission X but use Pongolian BMP's with new decals.
As far as competitions go, well MacGuba speaks all for itself. A single (and granted an exhausting) marketing campaign of "Beta Mission Party" brought god knows how many more submissions in. A LOT!
As far as prizes are concerned, I could think of some things that may attract:
specific addons or scripts made available only to submitters. (and later released to Joe Public)
perhaps a variation on that theme that the addon has to be used in the submission. (maybe a catch 22 there)
specific missions made available to submitters (prior to general release, god, we have enough good ones)
A hall of fame. A mec entry type competition, or some other device, where only the best will get on that list (for download). un-impossible eg, abandoned-armies eg and now, your-best-mission eg. I'd only choose 1 in 500 though to ever get in there
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