  We present a case for significantly enhancing the utility and efficiency of
the ngEHT by incorporating an additional 86 GHz observing band. In contrast to
230 or 345 GHz, weather conditions at the ngEHT sites are reliably good enough
for 86 GHz to enable year-round observations. Multi-frequency imaging that
incorporates 86 GHz observations would sufficiently augment the ($u,v$)
coverage at 230 and 345 GHz to permit detection of the M87 jet structure
without requiring EHT stations to join the array. The general calibration and
sensitivity of the ngEHT would also be enhanced by leveraging frequency phase
transfer techniques, whereby simultaneous observations at 86 GHz and
higher-frequency bands have the potential to increase the effective coherence
times from a few seconds to tens of minutes. When observation at the higher
frequencies is not possible, there are opportunities for standalone 86 GHz
science, such as studies of black hole jets and spectral lines. Finally, the
addition of 86 GHz capabilities to the ngEHT would enable it to integrate into
a community of other VLBI facilities $-$ such as the GMVA and ngVLA $-$ that
are expected to operate at 86 GHz but not at the higher ngEHT observing
frequencies.
