I have read several times that this is a shift from years ago when we didn't have them.

I'm going to work the late shift and go by the bank at 4pm.""

If it is not inside their unit or in a common area obstructing there passage you are not interfering with reasonable enjoyment.Only possible exception would net if they are shift workers sleeping during the day.Why do you feel any discount is warranted.

https://www.coachcarson.com/big-shifts-ahead/Above is a good article and book review from Chad Carson, a BP blogger, on demographic shifts. 

Just surrounding yourself with experienced people will shift your mindset.

Right now, for the leak, I'm doing everything I can to make sure something isn't wrong with the house (which I'd want to get fixed anyway of course), also because I feel that burden of proof has shifted to me.

A simple shift in insurance or a significant repair could send this property negatiive.

One way to lower the cost to buyer is to shift this burden and require the seller to convey in fee. 

Think about a few things when considering investing in upcoming cities 1) Current or future infrastructure projects 2) population shifts over the past 3-5 years and projected population increase/decreases 3) research the area on municipal websites, blogs etc see what people are saying about the area and what local governments plans are.

Trouble is if tax codes changes it’s going to be hard to shift the splits amongst partners.