Yup, I believe Ryo/Zane from season 1 is different than Zane from Season 2&3. His deck might be the same with minor differences, but his personality and lines are totally different!
As for season 4, he somehow returned to his older personality but still uses Cyber Dark deck.
could you add an event for umbra and lumis to unlock them as a playable character
Actually after looking into the Wicked Gods, I highly doubt Konami will put them in. While Duel Links is more or less a virtual game for the characters of the Yugioh series, it does seem to follow the show more than the manga. The only reason the Wicked Cards exist is because Pegasus died. Then again this is Konami so they may release them for the hell of it.