IMO GitLab should seriously stop with the features and spend more time in making the UI look decent and aesthetically pleasing.
You can follow the main issue here: https://gitlab.com/gitlab-org/gitlab-ce/issues/32794
Feel free to let us know your thoughts. This will start making it's way into the application in 9.4 (July) and will be activated through a feature toggle so people can experiment with the new UI, give us feedback and we'll iterate and improve it before we switch it over.
If you have any specific issues, feel free to open an issue or share them here so I can open an issue for you.