Firstly, taking Optimus Prime... calling him the same name, but making him a military reject AND making him a young rookie is wrong in so many ways that idiots who came up with that idea should be slapped across the face and the idiots who actually paid money to make them should be punched in the face.
Secondly, the art. Transformers like Star Wars has always been associated with high tech and good art. Granted the old series wasn't cutting edge art but it was still good.
And in modern times, after Armada, Energon and Cybertron, there truly is no excuse to make a backdated artstyle to create an animation who by the sheer premise needs have atleast decent art.
Thirdly, the characters. Sure the other characters might be bearable but for how long !? The Sari and Sundak characters are created by some hack writers who probably thought that they'll make their mark on the Transformers world. Guess what, you guys are no Bruce Timm [DCAU] or Greg Weisman [Spectacular Spidey]. Without Sam 'Spike' Witwicky. The human aspect of the series is very much gone.
It's like Spider-man without Harry Osborn or Uncle Ben.
Or Batman without Commissioner Gordon.
This show just went wrong in so many ways from the start, and having it focus on the younger viewers by dumbing down the story didn't help either.
Look at AVATAR and SPECTACULAR SPIDEY. Two prime example of how to make a show for children without making them stupid.
On the story front I'd have to say they did very good, along with the amazing the voice cast. Too bad the stroy never truly went anywhere.
You don't get to see Prime become the legend he's suppose to be. Spike never entered the picture.
No legend of Unicron... the faults go on.
In the end, this is a ba$tardised version of Transformers fused with Smallville probably 'cause the writers thought it was cool and that people would care about a young Optimus. Problem is, people does, if we saw this new young one slowly turn into the legend.
That never happened, so we didn't care about the show either.
I genuinely think there was a brilliant story and styling hidden underneath this children cartoon. They just couldn't rightly find that sweet balance.