Sure, we can discuss this further tomorrow, after the build will finish. I believe that Boost issue should be resolved now and Netgen will likely need to get disabled too. Best to wait for the logs to get produced first.
If you will click on the last link @sgrogan provided, there are build jobs listed. Clicking on one of them should take you to the log for that build job.I browsed around the travis-ci a bit but couldn't find a failing build.
P.S. As for changing the matrix, quick search indicated Bionic isn't supported yet on Travis, hence Py3/Qt5 builds aren't a feasible option for now. Updating to Xenial and having Py2/Py3/Qt4/GCC/Clang in the matrix, using OCCT 7.3 from the stable PPA. This therefore is the set goal for now.