These are all things that would be easy to fix. Jim Johston, WWE's resident musical composer not-so-extraordinaire, could be prodded into producing something new for 'The Viper' or outsourcing it to one of those generic bands he likes. Orton could grow out his hair or shave his head completely. The latter is something he flirts with on occasion but never goes all the way with, always retaining the closest of buzzcuts.
Some different coloured trunks could be ordered. Orty likes a primary coloured squiggle on black a lot of the time and that's served him and many other wrestlers well. But it's dull and contributes to the overall dullness of Orton's character. Even something as simple as switching to white trunks could help give Orton an air of freshness.
He could work on his promos, debuting a catchphrase or altering his cadence. He could implement a new move, either a transitional piece or a submission finisher. The dragon sleeper's free and I feel that, accompanied by a body scissors, would fit well with Orton's character. In longer, more important matches he could even target his opponent's neck, softening them up for the dragon sleeper and the RKO.
Imagine how much good it would do Orton to take a month or so off TV and return with a new haircut, a new submission move, new entrance music, and a lively, spirited promo style. He would seem like a new man, which may encourage people to show some interest in him. That in turn may encourage Orton to start tying a little harder.
It's notable that John Cena, a man who's been around as long as Orton and enjoys the same level of status within the company, continues to switch up his move set and makes a point of introducing new merchandise every few months. Yeah, the T-shirts are there to keep the money coming in more than anything else, but it helps Cena's look to constantly change. It's something Orton really needs to work on but he won't. Because of complacency.
Yeah, complacency will stop any of my suggestions from coming to pass. Orton knows he's guaranteed a certain status within WWE no matter. He has no reason to try and impress anyone because he has nothing to gain from it beyond the respect of people he very likely doesn't care about ("internet smarks"). Orton and his bosses are happy with how he looks, acts and wrestles. Therefore we're stuck with the same routine we've had for years.