Hi Hans,
It's normal on a local installation on a pc or mac. Many people report slower response on localhost. There are things you can do to try to speed it, but they are rather complicated.
If you can get a commercial server to try it out on, you might find it faster. (Unless it's GoDaddy, which may have speed problems because of the way they do things.)
Using a sub-theme shouldn't have any affect on the speed. Mostly the speed is affected by calls to the database, or scripts that need to load, large images or files that need to be read into the page by the parser.
Cheers,
Ed