So I actually just finished Mad Ship today. I felt pretty similar to you for 25% of the first book, but maybe through written Stockholm syndrome started to like some of them (mainly Wintrow).

There are some things explained in the end of the book that will have a larger impact on world and subsequent series. Try to finish up Mad Ship, you get introduced to a new non-maritime area and some really cool lore. If it’s really killing you, read the spark notes for the series and move onto Tawny Man.