Well, i use to use Fuji Astia 4x5 & 8x10 with strobes. That gave me a very nice but rich color transparency. If the client wanted "pop" then Provia. And if some real strong colors and contrast? Velvia.
The one thing you need to be aware is oil paintings. They can give of glare where the brush strokes are. I then used polarizes on the lights and the lens. Lots of tests! Water colors, cryrons and pencil drawings were easy.
Now, I don't even know if Astia or Provia is still made. But they were the best! I did a comparison between Fuji to Kodak and my printers and I and the clients all agreed that Fuji had it down pat.
you may also check into Fuji's color negative. It was so easy to work with.
Boy, I miss mt color lab days!