The unberable weight of a cumbersome plot: will it crush The Luminaries

Eleanor Catton's The Luminaries is, or appears to be at 100 + pp in and 700 + to go if I do go, not a Victorian novel but a pseudo-Victorian novel, perhaps a parody of the Victorian novel. It's got the trappings: it's long, a large cast of characters, a wide range (or at least a range) of social classes, an omniscient narrator - but what it doesn't have I think is a commitment to realistic portrayal of the social, psychological, and political dynamics of a set of characters - a family (Great Ex.), community (Middlemarch), a society (Vanity Fair), to cite some landmark examples. The plot is so cumbersome and elaborate, involving murders, purloined wealth, false identities, disappearing siblings, a hermit and a prostitute and a tattooed Maori, false shipments of gold sewn into the linings of women's clothing - and I could go on - but honestly who can follow this, and who is meant to? Increasingly, I feel we're just meant to laugh at these plot mechanics - narrated so tediously and clumsily in the early pages, before we know or care about any of the characters - and move on and pick of the atmosphere of this remote NZ gold rush town, Hokitiki (I think). Establishing atmosphere is Catton's strength - the rain-soaked and muddy streets, life on the docks, the down-at-the-heels men's club - and she's also good at sketching in characters quickly: the Irish Methodist priest living in a tent because no housing's available, the proud and highly intelligent and underestimated Maori - but what will she do with these skills? Can the novel maintain a pace or will it collapse under the unbearable weight of its cumbersome plot?