Mod Bod, Just saw your comment about Sonar adding "me too" features. I see it a little differently.
There are various types of users (and some of these overlap):
• Self-contained writers-producers
• Producers who record bands
• Producers of loop-based dance music
• TV/Film composers
• Songwriters
• Users who depend on or prefer virtual instruments or in-the-box mixing
• Those with a good deal of external gear
• Studio-based users
• Portable laptop recordists
If a DAW specialized in providing a solution for just one or a few of these groups, the DAW market would become very fragmented. Every time a producer or writer took a new direction or wanted to try something new, he or she would have to buy, configure, and learn a new tool.
For example, there a people here who vehemently argue how pointless a Staff View while I, on the other hand, cannot imagine composing in a PRV or Matrix view—but I do not want Cakewalk to drop support of the PRV or Matrix views just because I don't use them often right now.
To your point about support and development costs, if a function has few users, then I doubt it has many bug reports or requirements to handle.