A Rigid String Theory should also explain different types of standard and exotic particles like Glueballs. (30-100 GeV?) see below.
See also
Lubos Motl:
CMS: a locally 2.8-sigma diphoton excess at 95GeV
https://motls.blogspot.nl/2017/09/cms-locally-28-sigma-diphoton-excess-at.html?m=1
Other rigid string examples for massive Higgs particle series:
