Those Salzman 3m spoke reflectors are a great idea. I ended up making some myself by using 3m tape and a plastic coffee straw, but next time I'll probably buy the real thing. Of course, if you do not have box section rim or rim brakes - putting the tape directly on your wheel works great too (the deeper the rim, the better). I typically put a reflective stripe on both sides of my valve stem to make it easy to see where the stem is - and make the wheel reflective.

REI lightweights. I started off with those years ago, but realized the price was insane. $15 for something tiny, when I can go to an auto store and get four 18" strips for $5.
https://www.pepboys.com/pilot-automo...roduct/1746967

and yes, the white is very bright. The Black is fairly dim.
The black 3M tape is about as bright as a license plate
The white 3M is as bright as you are going to get. Well, its as bright as the white on a highway sign.