Each program has it's quirks and each has it's advantages over the others. Harvard was my favorite program for several years, due to ease of use, especially with the creation of tables, charts, and graphs. Harvard does not require you to launch another program to create those slides as PowerPoint does. In addition, Harvard lets you easily edit the chart colors and text colors unlike the cumbersome method that PowerPoint uses. For graphs, Harvard Graphics rules.
Drawbacks are with the color schemes of some of the templates.
The color combinations have been rather odd for years, but they can be easily edited and changed for your purposes. Freelance 2.1 had the coolest background templates of all 3 programs. It also lets you easily create and edit slides, but the graphs are slightly more cumbersome to manipulate than Harvard. I used Freelance when I needed a background with a certain theme and when the subject matter was not quite as serious. No fix was ever offered by Lotus, to my knowledge.