1000 Bulbs is one of my first choices for specialty lighting items, and I rate their quality second to none. This is my experience however and YMMV. I've used several types of their rope lighting for various projects involving soffits and crown molding that's back lit and the customers have been quite pleased with the output of the products. That said, brightness is a bit subjective. The commercial "ultra bright" is definitely a cut above most light rope for brightness but runs 7.5 watts per ft versus .5 watts for the LED and 3 watts for the standard. The commercial grade and LED are comparable in brightness, both what I would consider "standard off the shelf bright". About half the jobs I've done with the commercial grade the customers have requested dimmers. But, again, this is subjective. If brightness is a real issue you might think about using the ultra bright and dimming to your liking. The LED variety isn't dimable. Your link doesn't bring up a specific product and neither does a search using the numbers.

Cove lighting - In most situations, line voltage lighting like the Phillips eW or other bars would work well. Take a look at the ColorKinetics website for ideas. Line voltage fixtures could result in some savings since there is no need for low voltage power supplies or the need to run correctly sized low voltage wiring. Dimming would give you some flexibility in setting the mood. UCL The individual dots of light are less noticeable when the kitchen is really used since 1. There are items on the counter top to obscure the dots. 2. You get used to them. Some will spend on uniLume bars knowing that they are paying for a high performance premium product. With hindsight, I would probably go the uniLume line voltage route today since 1. Brighter output with no optical effects caused by the discrete output led elements. 2. No remote transformer (power supply) or wire sizing exercise.

I've never had a client complain that their undercab lights were too bright - go 400 to 500 or higher, but look for a dimmable system so you can turn them down for a dinner party. And be careful with the brand you select. If you go with the cheap ones from Amazon, they produce a green tint to the light. A better brad like WAC has a much whiter light, a better cri, and a lower failure rate. Tresco is another brand - they offer the widest variety in selection, color, lumens, and mounting options. As you plan the system, make sure you can get to everything and replace components if needed. The transformers are the first thing to go, but the leds do have a failure rate as well.

Light color temp is a personal preference. personally I like the cool lights. I have them in every room. They are the closest to sunlight. I love the windows in my house flooding in the natural sunlight during the day and want a light that can get as close to sunlight in the evening. I don't find them harsh at all, but cheerful. IMO everyone is use to the old warm lights and aren't use to a bright lights.