I’ve had really good success with code 250 and 215 Llagas track with my layout. Because I’m a cheap donkey, I handlayed my track and build my own turnouts. I use cedar fencing cut into scale 8x8 and cut to length. With a few bucks on a 1000 spikes, a rail bender, track gauge, and some rail I can crank out a 6’ piece of track in a couple of hours or less. Granted the first time I did it I was picky and spent 8 hours doing it (http://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-undecided.gif)Point being that if your budget doesn’t allow for much flexibility hand laying is an option (if you choose that route). You will have to spend time respiking and replacing ties but I found that cedar ties lasted anywhere from 4-6 years without having any major problems. This was a layout that was floating on ballast with decent drainage. For a raised layout like your planning, the cedar ties should have more drainage, and thus last longer. Now that said, handlaying takes time, and it’s not for everyone.
I mentioned code 215 because the common misnomer is that the standard “pizza cutter” wheels will not work on 215. I’ve never had a problem on my 215 or the 215 at Dave’s (TOC). I like 215 because it represents a smaller size rail, and I think of track as a model too (hence I enjoy the hand laying part).
As for the rail bender, buy or borrow one. It’s well worth the time to get smooth curves with a bender. I have the old style single rail bender and it works fine, but the new dual rail benders would work on preassembled track if you cut any tabs that hold the ties together.
As for track type; if you’ve already got it use it. Why spend the time and effort trying to sell and recoup the cost of track when you could use it? For example I have code 332 brass from years ago that I could sell (likely at a profit), or I could use it as staging tracks in the garage? Staging tracks it will be. Again if you have access to a dual or single rail bender you can reshape track to your hearts content. For example when I first got into the hobby I was given 2 full circles of LGB 332 brass in 4’ diameter. I pulled the ties, and straightened out the rails, reassembled and voila now I have straight pieces. I straightened these out by hand, and quickly learned the value of a rail bender…(http://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-surprised.gif)(http://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-yell.gif)