Well, it would be interesting to see if anyone has seen any trends in all the different forms of radiation from the sun, though obviously you can’t get it over a time span that large. Indirect evidence of solar activity (including sun spots) from 6000 years ago sounds just a little implausible.
If you've got an hour and 15 minutes, I would highly recommend watching The Great Global Warming Swindle from Brit Channel 4. It presents the case for sun spot activity affecting the earth's climate.
The fact that the film won't be shown in the U.S. and that it's caused Goreys to go apopoletic suggests everyone must see it.