I played a witch to level 17 in Skull & Shackles. Pirate theme blended well, and I was the cook on board as well. Like others have stated, I wanted to play a utility over spamming slumber/misfortune witch as that is my personal style of play (I enjoy doing unique unforeseen actions vs what the min/max adepts tell you to do).
I avoided slumber, misfortune by taking things like "swamp's grasp" and took craft wonderous items to make featherstep slippers for the party. Enemy can't charge/take 5' steps yet my party can.
I concentrated on utilities with my hexes (water lung, prehensile hair, evil eye, cackle, scar on my party to heal, fortune, flight, cauldron, hag's eye, retribution, healing and major healing). And I swapped feats for hexes mostly. I managed to get a +1 conductive crossbow and inflicted retribution/evil eye on enemies at range after buffing/debuffing the party. I flew out of reach, dropped darkness spells and swamp's grasp with low level spells, and lightning bolts were my go-to damage. Spells became highly useful as the only arcane caster, and I supplemented spells with battlefield control.
The witch (like any class) can be fun/boring. It's up to you to be creative and understand your campaign. In a home brew world, you might just want to keep slumber if you are out alone picking poisoned mushrooms in the wild...