Uproot already returns you Awkward array, so both things you mentioned are different ways of saying the same thing. The irreducible complexity of data analysis is there no matter how you do it, and "one-vector-at-a-time" sometimes feel like shoehorning (other terms people come up with include vector-style mental gymnastics).

For the record, vector-style programming is great when it works, I mean Julia even has a dedicated syntax for broadcasting. I'm saying when the irreducible complexity arrives, you don't want to NOT be able to just write a for-loop

Just a recent example, a double-for loop looks like this in Awkward array: https://github.com/Moelf/UnROOT_RDataFrame_MiniBenchmark/blo... -- the result looks "neat" as in a piece of art.