I agree with you, many expected that the FP2 will be rooted like the FP1, but this wasn’t the case at the very beginning (you had to compile the rooted system yourself). Only in April I think they released the Open OS which is rooted.
However, it is easy to root the regular FP OS thanks to a third party hack (after all, the bootloader never was locked).
What I understood from Fairphone is that they cannot offer root for the software version which ships with installed Google Services (what I understand for legal reasons). However, Fairphone has the FP Open OS version which is rooted and GMS free, and I am sure that this is also what they meant when they told you in the mail that they will offer a rooted system.
Like the regular FP OS, the FP Open OS gets regular updates via the updater, and Fairphone communicated they also want to offer monthly updates like for the default FP OS. (This didn’t work in July, but before, so I guess they keep up their promise again at latest after summer, after the holiday season). If you want to root the FP OS through the third party hack, keep in mind that you have to root it again after every update. In this way the Open OS is more convenient, but I think when switching then once you will overwrite the /data partition, thus loosing data and having to set up the device again. This can be made more easy if you use a good backup tool, like for example Titanium backup.
So basically you have two options: Root the FP OS through the third party hack, or install the Open OS which is rooted without GMS.
If you still want to use Google services on the Open OS, you can do so by installing the GAPPS yourself.
Alternatively some people use apps from the google play store (e.g. through blank store or raccoon) and replacements for the google framework services (like micro g) instead of using google apps or GMS.
While some people have reported that GPS does not work on the Open OS, I use it without any problems. I don’t know about bluetooth, since I don’t use it.