It is impossible to match the number of divisions Manny Pacquiao conquered throughout his career by majority of the fighters and he was an exceptional talent and i have read about his childhood struggle and we are yet to know the amount of fights he had as an amateur. Both these fighters are regarded as legends by many boxing fans
Even if Mayweather can't match that, his record of being undefeated is far more better than Pacquiao's record. Remember that typical boxing fans look for the numbers not the achievements so in terms of numbers, Mayweather wins no matter how much Pacquiao fans root for him. If they ever fight again, I think that it will be the same as the one they did back then, very boring.
Mayweather might be trying to understand the market hype and he already tried to match up with others for exhibition fight but it attained luke warm response but a Manny rematch will be one of the biggest fights in history.
Those exhibitions already have a down payment to him and the attendance doesn't really matter because Mayweather was already got paid, and most fights are generating big money on PPV(Pay per view) events. Sure a rematch will be big but I don't think that it will happen anytime soon, a lot of young guns are aiming for Pacquiao too so this might need to wait.