How many wizards should a force run - for fun

Do you play with any additional limitations for force composition? I ask as it is possible to have a Orc Sharman with every unit -- even though at 100 points a pop there is little sense having that many. I house rule, one per force so in a multi-player game there may be 2 or 3 but no more. I assume that such an approach would also make sense with storm callers etc. What do you all think?

I house rule one Epic Hero for every 500 points of troops and one Magic User for every 1000 points of troops. This way you get one Epic Hero in a 1000 point game and usually an Epic Hero and a Magic User in 1500 point game. More of each if you want to play 2000 points or more.