Here's a mission to asteroid Psyche for you.
Psyche may be a core of a failed protoplanet and possibly contains vast reserves of metals suitable for mining. This would be a huge step forwards for humanity.
The real mission is planned to launch early October and will use SEP (Solar Electric Propulsion) which is a low thrust but high Specific Impulse engine, which measures out its thrust slowly but surely and also very fuel-efficiently.
We can approximate a SEP trajectory with OITS by exploiting many consecutive Intermediate Points (IPs) or alternatively known as Deep Space Manoeuvres. However when I attempted to do this, I found replacing some of these DSMs with planets (either Earth or Mars) resulted in more fuel-efficient trajectories albeit using high thrust rather than the low thrust SEP.
Never mind, may try it again sometime!