Well...yeah. Every losing party has a few bright spots. Gerlach, Shays, and Heather Wilson all survived 2006. Boren, Ross, and Giffords all survived 2010. But if 2018 is a big-ish wave (not implausible if Trump's approvals are perpetually sh**tty), I'd wager that 3/4ths of the Clinton Republican congresspeople will lose. People like IRL, Curbelo, Comstock, Coffman, Valadao, and Paulsen, all seeming to be electoral superstars, would be fighting for their political lives. Then there'll be all those people who sit in marginal Trump seats (like you mentioned) that would be toppled in such a scenario. Dems only need 24 seats total, though they should shoot for more like 35-40 to allow for ideological flexibility to account for the Collin Petersons and Kurt Schraders of the caucus.
....Also, Dave Reichert(R-WA) survived bad years for Republicans in both 2006 and 2008 and Jim Matheson(D-UT) survived 2010 which was a pretty bad year for Dems. Larry Kissell(D-NC) survived 2010 but got beat in 2012.
