Even though in Standard I will be able to add many cards from the ISD block and M13, I think it is a useful exercise to combine the five regular packs and guild pack from the prerelease and the six packs in the sealed prep selection and build trial standard decks with the combined cards.
When I put all of these cards into a single selection, I have more balance in several guilds and a good selection of playsets.
For Azorious I ignored some nice enchantments in the prerelease when I went with Golgari.
For Selesnya, the prerelease selection wasn't so great, but when combined with this newer selection, I have more cards to choose from.
For Izzet, same deal as Selesnya.
Rakdos combines better.
And Golgari, because of the prerelease guild pack and the mythic rare I pulled then, seems to combine the best.