As Ralf, the drinks creator, says, "The Batavia plays well with the pineapple and the gomme, and the sherry gives it depth and body" to produce a punch-style...
Very sweet - you shouldn't be surprised, since most of the drink is sweet liquid. Given the clear tiki drink connection here - batavia arrack, pineapple juice, pimento/allspice, with nutmeg dusting - I think I might like this better served on some crushed ice, do dilute the sweetness and stretch the intense flavors a bit more.