You'd definitly want a discrete graphics card, it depends on the level of video editing/gaming your looking for ( low end Radeon HD 7770 = ~$110/ high end Radeon HD 7970= ~$430)
Id personally upgrade the mobo to the z77 chipset for better gaming as well.
now if he was getting a 3570K or plan to get one to overclock, or want some of the features available in some of the Z77 boards like the built in wi-fi in some of Asus high end boards,the no. of usb3.0/eSATA ports, no. and/or space of the PCIe/PCI slots, etc. or simply for the build quality, then spending on a Z77 would be ideal. otherwise, a cheap B75 isn't going to have a lot of impact on gaming