Could the American Revolution have been avoided if the British had pursued different policies toward the colonies?

Maybe in the short run, yes.  But in the long run, there
was no way that this was going to be avoided, in my
opinion.

In the short run, the Revolution would surely have
been avoided if the British government would not have imposed the various taxes that it
did impose on the colonies.  It could perhaps have avoided it even longer if it had
given the colonies some actual representation in
Parliament.

However, in the long term, there was no way the
American colonies were going to remain as colonies.  They were too big, with too many
people and too much in the way of riches to want to remain subordinate to such a distant
government for much longer.

The best that could have
happened would have been for the British to give the American colonies the sort of
pretty much independent status that the later willingly (without war) gave to
Canada.