On a personal note, I really dislike frames where the bottle cage is mounted at some awkward midpoint along the down tube.
If the frame is a large size and you can sense the consideration for making it easier for riders with larger builds to grab the bottle, that's one thing.
But with smaller frame sizes, I really wish they'd position it closer to the bottom bracket instead...
There are a lot of frames out there that seem to miss the mark like this.

Absolutely tasteless positioning.
It's an aero frame (or rather, originally a TT frame)
but doesn't the visual balance look off?


So I added an additional bottle cage mount hole (at the bottom).


Perfect, lower center of gravity. Now I can use a longer bottle easily too.


This frame didn't have a bottle cage hole on the seat tube side to begin with,
so I was planning to mount it as low as possible as long as it doesn't interfere with the bottle and frame.
Even with it positioned this low, there's no issue with accessibility to the bottle.