It has been said but when Lex takes on Supes it is usually something he has been plotting for a long time. A plan he has worked on for him or for others he teams with.
When Batman takes out a super powered threat out of no where the writers always give us the same
'Umm.. Yea he has been thinking about this guy for awhile and just pulled one of the 50 plans he has out of his ass.'
If they are going to have him fight Superpowered and god like threats in JL and other books fine, he is their biggest hero so have him battle the biggest threats. I get it.
But dont have him side step a punch from Reverse Flash then have him bitch slapped in his own mag but The Scarecrow. (Not a real example but the spirit of what I said remains)
Either go all in on God Batman or dont. It is hard to explain why he is taking out "I am going to take over the Earth Space God of the month." With little to no help from the JL Just to have to call in The Bat Family when Two Face kidnaps the mayor.