Is part of your question about the pseudonym Carl Byng?  There have been
some very good articles on the question of whether or not SLC used the
name while working at the Buffalo Express.  I think he did, by the bye,
and I think he did it because he had trouble believing the Mark Twain
would last any longer than most newspaper comics of the era, a decade at
most.  With Bret Harte in ascendance and himself stuck in some godawful
outpost, he wanted a new comic identity through which to build new fame.