Building every settlement will consume your soul.
Settlement building could use additions like concrete walls/roofs, and a more intuitive UI. It would be nice to point at a settler and read their occupation within my settlement, rather than guessing or giving them a uniform of sorts. Also, more reliable snap functionality, specifically, one that snaps to the object I'm aiming at, not to another object at the very left of my screen. Also, clipping rules need to be laxed or removed by default. Finally, there's a futuristic light that is clearly meant to be a small table lamp... it only ever snaps to floors.
So really, DLC should include fixes and new building content. I could go for having access to the alternate power armor station as seen on the Prydwyn.