> our queries ended up being several lines long

Which is... perfectly normal for non-trivial needs.

> I ended the project with having some proper aggregates, only for that to be thrown out of the window by the guy after me.

How is that a Django problem though ? Sounds like a skill issue on your successor.

I get what you say, there's plenty of debates about ActiveRecord vs. AnythingElse, but in the end this one has its use and obviously has served many of us just fine. Different strokes... you know the drill.