Imo, It is way too early to suggest that Ben Hendo "isn't marketable". Keep in mind, he's only been in the UFC for 1 and a half years, and only has two title defences. The key factor that has been the reason why he hasn't blown up yet, is the fact that has no finishes in the UFC.
Honestly, I think attitude has very little to do with how marketable you are as a fighter. Take Cain Velasquez for example. I see Bens attitude and approach to fighting as being similar to Cain. He trains very hard and generally doesn't have too many bad things to say about his opponent. But whats seperates them is the fact Cain in the past has ran through people in the first and second rounds, while Ben hasn't had that type of success in the UFC.
Givin the time, and the right string of wins, I think anyone can be marketable.
I agree with this, basically it's dominance that makes for popularity not trash talk.
The marketing types will keep looking for gimmicks that make people popular, but the fact remains that the only thing that sells in combat sports is badassery.
Wanderlei could barely speak English and he was the one of the biggest draws in MMA for a long time. Chuck was a pot bellied mohawked guy who never talked trash and barely spoke above a whisper and yet he was the UFC's biggest star, and sold far more PPVs than Couture with all his "Captain America" marketing shpiel. Fedor was a humble, backwoods, potbellied, balding Russian guy without a word of English to his name, yet at one point he was the GOAT of mma and it's biggest star ever, rejecting contracts for millions per fight.
GSP is as clean cut and non trash-talky as they get, and he is the current biggest draw. Jones is portrayed as "awkward in the press" and "too religious" etc., but he consistently sells huge numbers.
If Cain was only popular for being Mexican, why was JDS so popular? His first title defense sold 550K, even though it was against a replacement and heavy underdog in Frank Mir. It's because he effortlessly smashed the entire HW div that's why.
People watch this sport to find out who the baddest men on the planet are, period. Nothing else matters, no matter what tools like Sonnen or Diaz try to say to justify being tools. There might be some small marketing elements like Lesnar bringing in his WWE fanbase etc. but in the end it was because he too dominated the existing champs badly and he looked like Thor.
Bendo's problem is simply that he isn't dominant or dynamic enough in his actual fights. 2 close controversial decisions and one grindfest are all he has. The recent loss to Pettis and close fight with Cerrone just peg him as a "champion in passing" to casual fans rather than the "Man, no one can touch this guy!" vibe most of the other champs have.