While we have learned that JW doctrine is a pack of lies, they do close up some holes
nicely to address questions like you asked.
WT doctrines say that Jehovah is a perfect balance of love, justice, power, and wisdom.
Sure, he could have destroyed Adam and Eve, and the spirit creature known today as Satan.
But this would be observed by the millions of spirit creatures. The bogus "legal issue" raised
by Satan would never have been addresses- Can humans rule themselves successfully
without God? Would humans serve God out of love, or only for rewards? (This issue was
raised in the days of Job.) Without addressing the issues, another spirit creature could
raise them again, perhaps millions of years later. So Jehovah was using his perfect justice.
By allowing thousands of years to pass, the issues were completely addressed and now
they are confident that Jehovah has the right to destroy the world ruled by Satan and
to destroy Satan (after the abyss and the final test of loyalty for perfected mankind.)
Every conceivable combination of self-governing by man has been tried. (Not true by the
way, but that's their story.)
The WT is stuck with the book the way it was written (the Bible) so this is why their
explanation is a bit cumbersome. But all things considered, it's like explaining how
a character in a television show was killed last season, but is alive this season- it was
all a dream.
My problem with the JW story- Jehovah did not allow Satan to "prove" his case. Jehovah
changed the rules at the flood, at Babel, at Sodom, at the Exodus, in the promised land.
Their explanation for the vast majority of that is that Jehovah had to protect the way of
salvation- the people set aside for a special purpose leading to Jesus. I say that the
people were on to something before the confusion at Babel. They might have been able to
pool the knowledge of all mankind together, but the putting people in different languages
and cultures has prevented man from getting along.
So, if you can start a Bible-based cult with a better story than the JW's, well- there are
people out there who will like your version of "the truth" also.