Standalone 'Chat' Interface
While I understand that one goal of Teams is to bring all of the tools under one UX, Microsoft should consider allowing for a break out of the 'Chat' tool for user experience. While there are a number of use cases, one simple example of need is where something is being edited or viewed in the teams UX and a 'Chat' comes in, if the user clicks to view the chat, they lose their place in whatever file or video they were viewing their their other respective channel. The preference would be to have chat in one window, and the Teams Channel experience in another.
Jared Pickerell - Troy Public Schools commented
As stated by the original poster, having Chat as a separate area in the Teams client is not productive for certain use cases. It can be a step backwards from the separate (and simple) Skype for Business interface.
I too understand Microsoft wanting to bring everything under one interface and am not advocating that Microsoft does a way with the current all-encompassing Teams apps. Sometimes you need a separate interface, or at least the ability to bring it out into a separate interface. I'd love to see MS do this and using Teams client for IM/Audio-Video chat makes me want to go back to Skype for Business or some other application every time I use it.
I also created a separate UserVoice request that is similar to this request but might go a step further than what your request is asking for. https://microsoftteams.uservoice.com/forums/555103-public/suggestions/38860165-streamlined-im-audio-video-chat-interface