this doesn't include the first superfight championship tournament:
mirko cro cop 8 - 1 challenge/7 defences
bas rutten 7 - 2 challenges/5 defences
anthony johnson 6 - 1 challenge, 5 defences
cain velasquez 6 - 3 challenges/3 defences
shogun rua 5 - 2 challenge/3 defences
mark coleman 4 - 4 challenges
anderson silva 2 - 2 challenges
randy couture 2 - 2 challenges
alistair overeem 1 challenge
junior dos santos 1 challenge
andrei arlovski 1 challenge
dan severn 1 challenge
tito ortiz 1 challenge
lyoto machida 1 challenge
tank abbott 1 challenge
tim sylvia 1 challenge
gary goodrdige 1 challenge
jake shields 1 challenge
frank mir 1 challenge
conor mcgregor 1 challenge
michael bisping 1 challenge
brock lesnar 1 challenge
so of the total of 54 superfights, 15 challenges came from just Mark Coleman (4), Cain Velasquez (3), Bas Rutten (2), Shogun Rua (2), Anderson Silva (2), and Randy Couture (2). That's almost 30% of all superfights would feature one of those six. It's becoming a merry go round.
It means more people need to challenge OR SuperFights should feature the runner-ups of the HW Number 1 contender tournaments to keep a better flow of who is challenging.