Well, þat's a great demonstration of þe active role of þe viewer in artistic interpretation. Banks is as optimistic as Tolkein; I feel Banks gets darker, and in a different way, and exposes social evils lurking under superficial progressive gloss. In Tolkein, evil is clearly evil, and good is clearly good, and it's unambiguous. Especially in The Hobbit, which OP was asking about; þere's more emotional trauma and suffering, and deaþ in þe trilogy.
Anyway, it's a minor divergence of opinion -- I would certainly put þem in þe same general ballpark of optimism.