I don't think there needs to be a Star Trek TV series at the moment. It seems the plan is to continue the movie model for a few years and a few movies more. Besides, as stated before, any TV show will end up being a spin off from the current continuity. During the Berman era, people complained about over-saturation of the Trek franchise, and if a spin off series (regardless if it is in the same era as Star Trek 2009,2013, or that timeline's future), you will get over-saturation again, at least as far as Paramount is concerned. Also, despite what fans like many of us here believe, to a lot of people (IE the casual Star Trek watcher, or post reboot watcher), the only "real" Star Trek is TOS, and a maybe a lesser extent, TNG. So for that reason, I don't think it is a good idea to do a TNG reboot series, or a series based on another crew in the same timeline and era as Star Trek 2009.
Personally, if a series "must be done," then I think a good idea is to take a page from the Clone Wars animated series. If Star Trek 2009 and Star Trek Into Darkness follow the real world time gap of 4 years, that means Into Darkness is just now entering the 5th year of the voyages of the Enterprise. There are potentially 4 years of adventures to be explored, and a CGI animated series is just the medium to do that: it would be cheaper from both the FX stand point, and the fact they can use voice sound-a likes for the crew, if the cast members of the movies want to charge too much.
But I would only support such a proposition if it were well-written, and targeted towards adults. I would rather see 12 episode seasons of quality episodes, than 24 episodes of mediocre output.