My Lego room is also in the basement with low ceilings (7ft) and no outdoor light. My solution, which I've been using for almost 2 years and am still very pleased with, was to hang a 4 ft fluorescent shop light about 6 inches below the ceiling and above my work surface. The light fixture I bought plugs into the wall, has a pull chain, and only required 2 small holes in the ceiling.
If you decide to go this route, make sure the light fixture uses T8 bulbs(efficient) and an electronic ballast(no hum). I personally like a very white light so I use bulbs with a color temperature of 5000k. Cool white bulbs are about 4100k and tend to be slightly pink. I bought the light at walmart for 15 dollars then went to lowes (best selection) where I got two bulbs for 8 dollars.
Hope this helps in your decisionmaking