This game is balanced around co-op. Attempting to beat it on the highest difficulties while solo will most often result upon frustration and death. Only two ships are helpful while attempting this: Gunner and Treason. The latter being DLC-exclusive, and also the singlehandedly most OP ship the game has.
This is the only ship you will be able to use to beat the game's infamous achievements that are definitely untested.

Play Jamestown+ instead. It doesn't solve everything but it's the most polished version, and it does have Treason.

The thumbnail on this video is my reaction upon earning the final achievement.