I did that one but by creating new "main" reports (since I wanted to leave the ALL reports alone) and then assigning these main reports as the default report, but thank you for the official method of doing this, less clicks in the future!
One other quick one, normally you edit the field value to remove the, for example, <add a new site> option (via "allow users to create new choices") but I can't remember where this option is for lookup fields? I'm pretty certain that also includes what information to display in the drop down (ie. record ID# + site ID or just site ID). I've been hunting but can't remember where this option is, can you point me the right way?