After watching TDI AND TDI more closely you can see that TDA is a better show (in my opinion anyway, don't slate me!).
In TDA, the writers gave fringe-characters more air time and character developpement. Justin went from a distraction to a manipulating fellow that adds the 'drama' and the 'unpredictability' on the show. They needed a new villain for Action, and with Heather already being found out they needed someone that isn't widely known to the other TDI characters and even us viewers. Who is better than Justin, who was open to ANY character plans because of his very little contribution in Island?
On that note, they should have brought back more fringe-characters, such as Ezekiel, Tyler and Noah and give them 'extra spice'. As much as I love them, Geoff and Bridgette are now past it, as is DJ, Gwen, Owen and Heather. LeShawna and Izzy could also be considered in this bracket.
Another change is Lindsay, who went from being manipulated to a new 'bossy'-stand-up-for-herself girl. That's fine, as now Lindsay could offer some new 'commanding' character to the show, and maybe, if god forbids, brings her team to a win.
The relationship between Duncan and Courtney, which I thought was past it, as actually surprised me so far. So many elements added to spice up the duo. It's great! Hopefully some delicious plot twists will happen in the near future.
As for the breaks, yes it's annoying but you need to learn patience. You might love this show to death but life has so much offer and you are missing out. I went a bit AOL and I will not deny that I am surprised that no new episodes were aired during my departure. They must have a good reason to do so and their decision will remain the same.
Island has humor but so does Action. Except, they are more 'inside-jokes' that needs you to comprehend a certain subject/joke for you to laugh. Island was more about the kiddy, simple jokes that you hear/see most of the time.
All in all, Action has more depth than Island. The latter proved to be too short for 24 characters so they decided to cut some loose but keep the same number of episodes, thus adding more time and creativity for the characters in Action. This is why I would have preferred characters such as Ezekiel, Tyler, Noah, Katie, Sadie and Eva over the likes of Gwen, Geoff, Bridgette, Owen, Heather and DJ.