The development team uses UserVoice to keep track of improvement suggestions outside of the Activity Feed. This provides direct access to the dedicated UserVoice system.
In order to participate, you will need to sign in using an account specific to that UserVoice system. Be sure to use your Planets.nu username.
On the right side, under your user name, there is a navigation box which lists the number of votes you have left (each user starts with 10), plus links to Post A New Idea, the list of All Ideas, and My Feedback. This last shows every comment you have logged, all feedback you've posted, and every vote that you currently have logged somewhere in the system.