As dclive says, I'd recommend just leaving the settings as-is. WHS is VERY efficient at making backups. In most situations, if you don't have adequate drive space, you'll probably have issues whether you back up once a day or once a week. Fortunately, hard drives are pretty cheap these days. And WHS' extreme flexibily in adding and removing drives from the drive pool make it super-easy to keep up with changes in storage needs.
I suppose the one exception to this rule might be if you are making lots of modifcations of very large files on a daily basis and backing up daily. Editing big video files every day, for instance. In that case, the daily incremental changes might be pretty big as those big files are modified and WHS has to keep backing up the changes to all those sectors. But I doubt this is how most folks use their PCs, at least not on a normal basis.
Personally, I find it very re-assuring knowing that every single day I have a backup that'll take me back to the previous day's System or data files. Or to the backup from two days ago, from a week ago, or from three months ago.