I know there is already some work on this, but here are my first impressions
When I build a factory, I want to immediately set the drone type and move on. Construction sites don't have the factory interface though. Work around is to find a factory producing default type and change that. Might be nice if I could do B, W, (drone type hotkey), but maybe that would interfere with other build sequences.
Although, with the shared unit cap, a new factory mostly causes drones to be built from old factories, at least in the short term.
The way things end up working, it might be better to have a global drone configuration similar to the always available build menu. You choose the ratio of drone type, and the ratio stays the same no matter how your cap changes. Doing the ratio on new production might be easier, but having it try to maintain your overall unit composition could be good as well.
An easy way to set rally point for all factories is something I've wanted as well. Might not work if you set up a forward base somewhere, but that is already pretty tricky with new units appearing at old factories and such. One way to manage this would be double-click or hotkey for all factories on screen, which would also make it easier to build a group of them.
