So these series are recommended for beginners as a quick way to get into the Gundam universe?
Yes! I listed the ones that you can simply pick up and watch.
After watching most of Gundam 00 now on Syfy (3 episodes to go). I recommend this one the most to beginners.
There seem to be a lot of stand-alone series for the Gundam franchise. Getting away from the continuation after continuation and going for the independent (or stand-alone) series, is this something new to try to pull in new viewers?
Yes and no! In Japan, it was to a certain extent. However, what created the switch was when Yoshiyuki Tomino allowed other directors to make Gundam series. Tomino sticked with one time line (Universal Century) and created loose continuation between the series, while the other directors didn't want to do that. Mainly, because they had new and unique ideas for the franchise. That's why they created alternate time lines and made them standalone.