Sounds like you have done your homework and have a good grasp on what you are going to do to start your pool. PoolDoc wrote that sticky as an easy way for people to start their pools, and most of those people will not have done their homework as thoroughly as it appears that you have. It doesn't mean every Intex pool has to be opened and operated by that plan.

Once you get your CYA up to 40-50ppm you can switch to using a non-stabilized form of chlorine such as bleach.

Sorry but I can't answer your question about the Intex vacs.

Hope this helps and welcome to the Pool Forum!