  Relativistic heavy ion collisions produce nuclei-sized droplets of
quark-gluon plasma whose expansion is well described by viscous hydrodynamic
calculations. Over the past half decade, this formalism was also found to apply
to smaller droplets closer to the size of individual nucleons, as produced in
$p$$+$$p$ and $p$$+$$A$ collisions. The hydrodynamic paradigm was further
tested with a variety of collision species, including $p$$+$Au, $d$$+$Au, and
$^{3}$He$+$Au producing droplets with different geometries. Nevertheless,
questions remain regarding the importance of pre-hydrodynamic evolution and the
exact medium properties during the hydrodynamic evolution phase, as well as the
applicability of alternative theories that argue the agreement with
hydrodynamics is accidental. In this work we explore options for new collision
geometries including $p$$+$O and O$+$O proposed for running at the Large Hadron
Collider, as well as, $^{4}$He$+$Au, C$+$Au, O$+$Au, and $^{7,9}$Be$+$Au at the
Relativistic Heavy Ion Collider.
