In my opinion, wheel building and selecting wheel components is one of the most over thought things in the bike world, even worse than which chain lube....
If you use quality components designed for what you are using them for, assemble them correctly, they will last a very very long time. I have built many many wheelsets with standard straight gauge spokes that have lasted until the rim had worn out from braking.
I personally always stray away from anything Sapim, I know people out there have had good luck with them but I have seen lots of issues with broken spokes from them on wheels with proper tension. I am a firm believer in DT or Wheelsmith spokes, my favorite are the basic 2/1.8/2mm DB spokes. I have never had any wheel built with them break a spoke yet, and I build wheels for a living.
Alloy nipples work just fine as long as you make sure to properly lube everything, if not, they can make your life hell bringing a wheel to tension. The only time I really push people away from them is if the bike will see a lot of corrosive environments or they are doing some major loaded touring. Brass is always nice if you do not care about an extra 30 grams though. If you are having issues with breaking nipples or are worried about that, proper spoke length (meaning the spoke comes all the way to the end of the nipple) is far more important than anything else.
I personally am running the WI T11 hubs with Velocity A23 rims on my commuter/road bike with basic DT DB spokes and aluminum nipples both 32h and laced 3 cross. I could have saved some weight and dropped spoke count a little but realistically I would never notice the difference since I do not race and tend to lean towards durability more than anything. The combo built up really well and there was nothing alarming with NDS tensions and WI hubs.
The 23mm wide rim is quite nice, I can tell a small difference in ride quality and how well it corners but it would not be a deal breaker for me to not have it. I also run the same rims on my cross bike which see's a lot of gravel grinders and even a good amount of mountain biking and they have held up great so far.