yes maybe you are right, current gain beta is a function of its collector current,
you can check this information on P.R.gray's book ,p115
and beta is also a function of temperature ,normaly beta has postive temperature co-efficience, so bjt have sef-calefaction. this is the reason that bjt power transistor is not used parallel to supply big current and need thermal protection circuit to protect the power transistor.
i am not sure if you have get your answer??