There is no cookie-cutter approach to all software products at once.
"I want classic sound / look / feel" of entertainment products like WoW is very different from, say, "I want old spreadsheet shortcuts / simpler UI" of office products where you have to actually balance many functional features that are in demand with simplicity and past product behaviour some of your users got used to.
Edit: I think I just rubber ducked myself with this comment into understanding that it is user segmentation which is key regardless of your product; real challenge is to try embedding and balancing all product features as a single package, instead of splitting core product into multiple different parts that fit different segments (like Blizzard did)
"I want classic sound / look / feel" of entertainment products like WoW is very different from, say, "I want old spreadsheet shortcuts / simpler UI" of office products where you have to actually balance many functional features that are in demand with simplicity and past product behaviour some of your users got used to.
Edit: I think I just rubber ducked myself with this comment into understanding that it is user segmentation which is key regardless of your product; real challenge is to try embedding and balancing all product features as a single package, instead of splitting core product into multiple different parts that fit different segments (like Blizzard did)