I would go for an interchangeable lens system, such as micro-4/3, because you can then choose from a wide variety of lenses that offer features like sub-f/2 apertures and, by adapting manual focus film camera lenses, short telephoto capability with macro focus. I really like the Lumix 20mm-f/1.7 lens, it has an angle of view equivalent to a 40mm. A sub-$50 lens adapter means your favorite old film camera lenses can be put to good use for no additional cost.
For motorcycle paint photos, you might want short telephoto capability like adapting a 50mm f.l. lens that yields the equivalent angle of view of a 100mm, and such a lens with macro will still work for close-ups, the cost of which is only the adapter, if you already have these older lenses.
Of course, there are a great selection of autofocus lenses to choose from in the micro-4/3 lineup, the best of any mirrorless format.
For lighting such projects flash has been the traditional way of doing it, keeping in mind that with micro-4/3 your sync speed is limited to a max of 1/160s. Not a problem in a studio setting, however many people are starting to discover LED light panels work well with the new mirrorless systems because you can also use them to shoot video, and you can preview the lighting effect live before exposure.
I wouldn't buy a camera for just one project, but would consider buying into a system that offers many lens options and bodies to choose from, like micro-4/3. The X100 is a good camera, but it isn't a system camera.
-Joe