Waiting for the download is an issue, but the size it's self isn't. I remember with Windows 95 having to worry about games taking up hard disk space, but I haven't had that issue in years, and have plenty of triple-A games installed. The size really isn't that big of an issue.
But I'd reinstall, as the single player missions are some of the best I've ever seen in an RTS. Lots of variety, and very thought out, however the plot is terrible.
