Good questions  LFS2.  However, as I'm sure you are aware, far too complicated for me to answer here.  The best single book I know is McLagan's "A Peculiar  Paradise", 1980, mentioned above by Pidgeon.  .  See especially chapter two, "To keep  clear of this most  troublesome class", on the exclusion laws.

For a more  recent book see Greg Nokes, "Breaking Chains" , 2013, on slavery in the Oregon Territory.  In discussing the  vote finally ending the exclusion law in 1926,  Nokes concluded:
"Oregon's long flirtation with exclusion  laws had finally ended.  But while the exclusion laws were rarely enforced, the tragic legacy of the laws was that they discouraged blacks from coming at all."  p. 171

I appreciate your sincere  interest in Oregon's racial history, LFS2 and will be interested in your views once you've read Nokes and McClagan or others.  As for solutions, perhaps you realize that the touching program at the Mim's house was part of the healing process.