X3 is a great daw for many (including me) but there's definitely still room for improvement in terms of usability. If you feel the same way, why not post your wishes here (up to 3 if possible, not to bore the reader) for small things that would be of huge help in your daily use of Sonar. Who knows? You might receive great advice or workarounds, or maybe they’re already possible in X3.
I've submitted quite a few feature requests in the past 12 months, about CV to PRV to Control Bar to some other areas, but looking back all the requests submitted, I think I can say that my top 3 inconveniences occur in the Track view, because it's what I use the most (and maybe because these inconveniences don't exist in my secondary daw).
#1. Auto track scroll (when double-clicking a clip to open a desired view) 
Sonar already has an ability to automatically scroll up/down tracks, which you can witness by showing MULTIPLE tracks in the PRV and clicking one of the tracks in the Track List pane on the right. Unfortunately, this auto-scroll doesn't happen when there's only ONE track in the PRV (which is the case when you double-click a clip to open the view). I've tried what I thought would be workarounds, but they all require at least three actions (
edit: I was wrong. brundlefly gave me a two-click workaround in this post) or a few-second wait to show the clip above the PRV for simultaneous editing of notes and clips. And no, I don’t use dual monitors.
#2. The "focused track = selected track" option 
As the screenshot indicates, a "focused track" and a "selected track" are two different things in Sonar. This is quite inconvenient because, for example, if you hit Alt+3 wanting to display only the "selected" tracks in the PRV, it also displays the "focused" track, which you don’t want displayed. Similarly, when you want to solo the "focused" track by hitting Alt+S (this is "Solo All Selected Tracks" and I have to use this because there's no shortcut key to solo the "focused" track), it solos the "selected" track(s). You could easily edit/delete clips on another track accidentally/unintentionally because of the current behavior. I hope there’ll be an option to change it.
#3. Option to hide the MIDI Editor indicator There are some things that make Sonar’s Track view not very beautiful (e.g. the big padlock icons, gray and uncustomizable clip name text color, each folder displaying its track folder name, etc.) but the most uncalled-for thing in the Track view IMHO is the “MIDI Editor indicator” in the upper-right corner of each MIDI clip. This indicator was introduced in X2 as a handy feature, but honestly, do you use it? Me? NEVER. I wonder in what situation you would want one clip to open the PRV and another clip in the same track to open the Staff view or Event List or Step Sequencer view. I use lots of short MIDI clips and this MIDI Editor indicator often blocks me from opening the PRV when I double-click the clip. Also, take a look at the following two screenshots. You can see how easy it would be to read clip names if there wasn't this indicator in each clip. I really want an option to hide it.
With the indicator
Without the indicator
Thanks for reading. I hope my wishes will come true one day…