@Quentin Mitchell. Your list is a good start but I'd like to elaborate a little from the contractor side. First, attitude is everything!! If the team that you work with has just one person that makes everybody's job more difficult than there will be wasted time and time is money.
Second, although you want to get the best rates from your contractors don't just go with the least expensive. Those are usually the ones that will cost more in the long run. Also make sure that each trade is supplying estimates based on the same things, so you're comparing apples to apples so to speak. To help this, make sure that you have everything you want done listed and give that list to each contractor for that trade. Make sure that they are using the same materials and finishes too. If one is using hardwood trim and the other is using pine trim that will reflect in the estimate and will create a skewed comparison.
Lastly, references are always good but you have to take them with a grain of salt. Trust your gut instincts. If you have a hard time communicating with them then it's probably not a good fit.
Best of luck!!