It's fair to say that the ME-02 and VA-07 polls should be questioned. Are they one data point? Absolutely. NYT/Siena is doing a great job. But it's not "unskewing" to purely say that the samples are off ("Nonwhites" going to Republicans in ME-02 by like 20%?) The samples are so small that the entire poll is not 100% indicative. Same with VA-07 and young people.
FL-26 is surprising, more so because Curbelo right now has such an amazing favorable rating and the D is unknown. However, it's a Clinton +16 district, so it's also not entirely surprising to see partisanship win and have the D up.
ME-02 has a de minimus amount of nonwhites to start with though, studying inaccuracies in polling such a small subgroup is a triviality.