Oberon, this is potentially a huge discussion as there are so many factors and options out there. I'll just make a few points about strip lighting.
Rev's amazing display uses the Ikea Dioder solution, which emits a warm white or yellowy tint to it much like an incandescent light bulb. It's basically plug and play, sort of. Mine is all custom and requires a lot of effort. It uses bright white LED strips on a reel, much like what you are considering. If you are willing to put in the work, it's well worth it.
In general, you need to decide what kind of white lighting you prefer. The Kelvin rating is key and determines which kind of white it will display, warm white or bright white. Don't get too hung up on LED size as they all emit plenty of light for a typical Detolf display. Some maybe even too much. Rev always refers to my man cave as my sun room
The other thing to consider is the RGB connectors and respective strip lighting are wider than the 3528 solution (what I use). It sounds like the visibility of the underside of the strip lighting as you look down on the shelves will bother you. Well it will be more intrusive with the 5050s. I have considered hiding mine with a strip of decorative tape but it doesn't really bother me.
As far as configuration/layout, I have tested this thoroughly and IMO the |_| shape is the optimal layout and minimizes shadows. The cut points on the strip lighting are perfect to achieve this.
As far as dimming, don't bother. I tried it and it's a pain to get working and will just complicate your wiring IMO. If you must have it, go for the ready made solution.
Hope that helps.