I think the point of the chart is that it is supposed to be a tool for reflection. The peices are not representational.(Come on, they are going to tell you recreational activities should take as much time as personal study?) The Watchtower knows better than to explictlly tell people how much time to be doing what. You are supposed to look at your life and adjust the sizes accordingly. Then take a good look - which piece is the biggest, which one is the smallest? Does your chart look like what it is supposed to look like? Well, then, you know what to do....This is how the Watchtower works. They tell you what to do without telling you what to do so they can say "We never told you to do that."
Of course it is designed to make you feel bad. You only have 4 worthy options of how to spend your time. Which is completely unfair and unrealistic. And the majortiy of that time is for "kingdom related activitites". Excercising, shopping, emailing, gardening, watching TV, reading, chatting with friends, enjoying fresh air, visiting family - anything that you enjoy, that makes life worth living - all fall into the category of "recreation" which we all know should be the smallest slice of pie. So, each week you are allowed maybe 2 hours that you can fill with one of the options from the above mentioned list. But, hey, they never said that.