I'm a bit late to the party as well. I think all of the ideas are great, but as with so much with this hobby, not every thing will appeal to everyone. I like the idea of a terrain contest, but as others have mentioned, it is a bit of a subspecialty within the hobby and may not get a lot of attention. The writing bit is of particular interest to me--I would love to see something implemented regarding Wyrd fluff; that has always been of interest to me since I am more of a painter as opposed to a gamer. I think the opportunity to be a part of something like this would be a great thing indeed and I was moved to do a little bit of writing (something I had not done for a good 20 years) a while back when there was a fluff thread going.
With regards to the painting comps, more is always better for those of us sitting in the wings--having something always coming up is nice. That being said, I would have two concerns for the Wyrd folks. One is participation. The more contests you have, I think the higher the likelihood of a (relatively) poor turnout. I recall one of the HH contests having a lower showing than usual (in the 30 range if I remember correctly) and there was at least transient concern that the contests were losing their luster. Adding more to the yearly mix may aggravate that. The second concern would be financial (not any of my business, but I'll voice it anyway). I have no idea how much it costs the Wyrd crew in swag and prizes, but 3 winners per category plus BoS and BoW and random schmuck prizes AND voting prizes would seem like it would add up. If you did add a contest or two I would have them heavily (or entirely) Wyrd based to help offset the generousness this site has shown time and again. The time and effort invested in putting these contests together also has to be considered. I think this site has the best online contests in the community, bar none. I would hate to sacrifice quality for quantity.
I understand the need to keep things fresh and I know that if the past few years are any indication, these new ideas will be well thought out and just add to the Wyrdness I visit every day!
*Edited for extra rabid fanboi appeal*