[diybrewing]

I have judged in a bunch of competitions and 40's are a rarity so I would start by saying getting high 30s is where you want to be.
People have gone over the good stuff like temps and starters but I will throw a couple of more in there too.

1.Get a good appreciation of how the grains taste before going into the brew. I have eaten every grain in my homebrew shop and that is a huge help when formulating beers. Go into your LHBS and ask to taste some of the grain or ask if they do any classes that involve tasting of the grains ( we do and I think other LHBS do that too)
2. Brew more often. The more you brew the better you will be. You should also try tweaking your techniques occasionally to see if they make a difference.
3. Work on one recipe until you feel it is perfect. Brewing a large range of styles is great and highly recommended but if you want to make a truly outstanding beer brewing 5 times in a row with minor tweaks is the only way to go.
4. Join a homebrew club. Homebrew clubs are the place you want to go to get better.
That is the only ones that I have noticed that I think are missing.

[rbclay]

I think we may be in a similar boat. I am an extract/partial mash brewer also. I was fortunate enough to take first place in the Midwest Region for Nationals this year for my APA. It made me happy as pigs in $*%!. I didn't medal in final round- but I made min-BOS, so as far as I'm concerned I got 4th place!!
In my opinion it takes more than a bit of the luck of the draw to win contests. But it also takes brewing very good beer. By your scores you already do that. A lot of good advice in the replies I read above. My advice is this- review Mark Tanner's presentation from this year's AHA Conference. I am a committed extract brewer. I saw his presentation in person. I want to win contests and Mark has done so as an extract brewer for years. I assume by your question you want to do the same. By all means if you want to go all grain, make the jump. If you want to improve your current technique, check Mark's advice and feel free to contact me.