I really like Feraligatr and its a really strong Pokemon once it sets up. Your team is pretty well made with defined roles for each Pokemon, so your team is pretty efficient already. There are a few kinks that I'll try to help with.
On Nidoqueen, I do realize that the accuracy of Flamethrower is its biggest boon, but the power loss isn't worth it. Your team hits fast and hard and Fire Blast is a good alternative. The biggest drawback is obviously the accuracy, it might come to bite you in the back with it misses.
On Spiritomb, I don't think Choice Band works the best for it. With Choice Band, you can get locked into an unfavorable attack like Sucker Punch or Pursuit, which then can be set up on by sweepers like Klingklang, Moltres, or even Sceptile. I don't recommend changing Spiritomb though, as its a great spinblocker and it works well with your team, and takes out Slowking which is a roadblock for Feraligatr. I recommend BlackGlasses to replace Choice Band, and changing Trick to Will-O-Wisp. BlackGlasses still gives you the umph you need to Pursuit and Sucker Punch without the implication of locking into one attack. Will-O-Wisp is great to catch physical attacks like Escavalier and Kabutops, which could otherwise be problematic for you.
Hope I helped n.n
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