My 2 cents (Not that they mean much.)
1. 32 bit client is easily detected since you have to manually change it to make it 32 bit.
2. Being that I only use Enyo and Custom CRs, I believe the overlay's are a major issue and should be removed. This is something recently added and its also how the PR ban hammer happened.
3. I'd like to see 2 different versions of HB. One that is like an Enyo stand alone, only used for rotation botting, and a second version for questing, pvp, farm ect. This way if another ban happens, if people choose to only use one or the other, you can narrow it down to which is being hunted if only 1 of the 2 get banned. If both get banned, then its because they are using HB source to detect it.
4. They banned by IP. Once confirmed 1 account was using, they just banned all of the accounts linked to that address. My GF and my Roommate both got their accounts banned (they don't have HB on their computers) along with 4 other of my accounts (2 that I haven't used in over 3 months).
4. In order to remove all doubt, if you have already been banned, you will have to wipe your computer and change your static IP to make sure that whatever was on your computer is gone and you aren't linked to your banned account. Personally there are plenty of ways to detect someone using HB since an employee of blizzard could easily be on the forums and get access to all the code they need to do a "search and destroy" action on any code being run identically to what is coded in HB.
5. Personally I figured HB was perfectly safe for how I was using it (just as a rotation bot), however I was wrong. I made the decision to use it on my main account and I paid the price. I will be buying another account and will be using HB once it is up and running. If I get banned again oh well. However it is my choice to do so. I will stick by HB as long as it is in production.