Just learned about the TAB+F3 trick to enable frame buffer support (see improvements illustrated in attached screenshots). Performance improved, system also didn't get so hot while running game. Was able to run game for ~8 hours without issue.
Then I relogged...sad times.
Error at startup (also note typos in error message; first word is missing an "e" & additional uses of same word are spelled correctly but with lowercase "b"):
FramBuffers are not supported on this Graphics Card. Framebuffers are used for effects like bloom. Continue without Framebuffers.
Intel Iris GPU: Late 2013 13” Retina MacBook Pro w/ 2.8Ghz i7, 16GB RAM, 1.5GB shared to GPU.