Definately not too advanced for you. It is the perfect choice to take your riding up to the next level as it is super light and will give you amazing control. There's a reason it is hands down the most popular women's board ever made - it goes anywhere and everywhere. One of my friends went from intermediate to advanced in one weekend after buying a feelgood. If you went with a lower level board, like the feather, you would surpass its abilities within a season or two in CO. So go ahead and get the feelgood, it's the only board you'll ever need! And if you're going to be riding a lot of powder or fast groomers, opt for a size larger (more towards nose height than chin height) to float better.

This boot is Burton's top of the line for advanced riders and is a little on the stiffer side. I would opt instead for the Burton Emerald, their ultra all-mountain boot. It has a flex(stiffness) right in the middle of the scale and is great for intermediates looking to advance. Another very good option is the 32 Lashed. 32 specializes in just boots, so they take comfort and quality seriously.

I would go with the 138 or 142. Your board size has more to do with weight and skill level and in your case foot size, than height. A smaller board is for a lighter rider and/or for park/pipe use. A longer board is for a heavier rider and/or for all mountain, carving, back country, etc. Smaller boards are lighter and more manueverable (easier to control), but longer boards float on powder and are more stable, especially at higher speeds. If you are a beginner, go for the 138, it will be easier to learn with, then upgrade to a larger one when you get to an advanced level.

A lot of the mainstream brands, like Burton, do not make size 10.5 in women's. Try Northwave, Nitro, or Head. Is 10.5 your street shoe size? I recommend going and getting professionally fitted at a ski shop because most people should wear boots that are .5 or 1 size smaller than their street shoe size. Also, brands fit very different from each other, so go try on everything in the store, then go online and buy what you found fit just right. Whatever you do, don't buy men's boots! They will not be comfy because they're the wrong shape and proportions.