I grew up in the Richmond area and agree you could see most of the best/pertinent sites within a day. I would personally stop off in DC to spend the majority of your time there and then take the train from DC to Richmond.
As stated above, Richmond does have:
1. Great beer (The Veil, the Answer, Triple Crossing, and Final Gravity) located within a 10 mile radius of one another.
2. A few interesting restaurants in Downtown, the Fan and Carytown. I'd recommend the Roosevelt, L'opossum, Barrel Thief (mainly if you like wine), Edo's Squid (for great seafood based Italian fare).
3. A fine museum in the Virginia Museum of Fine Arts. I would also check out the Anderson Gallery at VCU, as it has had some significant artist's work in the past (namely late Warhol) and posts student art from one of the better art schools in the US.
4. Historical areas, such as Monument Avenue, the Edgar Allen Poe Museum, the capitol area, etc.
5. An absolutely beautiful estate turned into a public park called Maymont; I'd highly recommend this if the weather is nice, as the estate is beautiful.