This series was good, I wish it were finished. Instead it seems it's gone the way of SMBZ.
I guess I'll give my opinion of the series over all from what we've all seen.

Sonic Origins: 3.0/5.0 Emotional and inspired though lacking in the quality department. It was entertaining and enjoyable for the story and ambiance more than anything else.

Sonic Rise of the Brotherhood: 4.5/5.0 Parts of this part of the story rise into 4.5 territory, the jokes with Tails, Tails and Amy, and the death of Sonics bro all rate pretty highly on the good entertainment scale, for comedy, comedy, and drama respectively. The animation quality is much improved+++ so that's always good.

Age of the Brotherhood: 3.5/5.0This is where the fight scenes especially start getting respectable in the animation department. The reason the rating is lower than Rise though is because it feels incomplete as an independent story in a saga compared to Rise, probably because, it is incomplete.
For what's there though it's still one heck of a ride. Now as for the series, all three of them as a whole I can't find it in myself to give it a 3.5/5.0 because I enjoyed it more than that, the whole is more than the sum of it's parts anyway so I have to give it all (what's finished anyway) a 4.0/5.0. Maybe if the story were to be completed and were continuing its trait of upward incredibility it could've gotten a 4.5/5.0. Just like if SMBZ were completed it would've transcended the boundaries of space and time but I digress, this was good work you did anyways, and I'm sad to see it dropped, good luck in your future creative endeavors,
S man OUT!