Team Ideas Development with Collaboration

My team is constantly looking for process improvement, but BAU kills any chance at focused project work. 

We are looking for a solution where we can identify an area of improvement, where we can all lodge ideas for a solution, comment on each other's ideas, and develop the solution until it gets to a point that we have a solution we can take to executive for implementing. 

"Employee ideas" isn't bad, but you can't develop on from an idea, only vote... so employee ideas... but more....

As a public agency, we can't use any additional/unauthorised apps, so it needs to be something native within TEAMS.  I've looked at Power Apps, and I'm willing to extend an existing app if there are any clever people who have published a solution like this. I saw one about linking back to the message thread, but I really want the discussions to show on the idea as I expect the solutions to be a little more complex. 

An example. we want to set up a way that makes it easier to locate information in our records management system, we can use electronic boxes (where we associate all files to however many of the boxes that apply - subject matter, stakeholder, product etc) or we can have user labels/tags that do the same thing and are quicker to associate, but don't migrate if there is a change in corporate structure. Even if we choose one or the other, what "labels/boxes" are needed, what naming protocols, and suggestions for procedures for new files etc etc. so as you can see, not just a list of ideas, but solutions with multiple elements, and not all the same elements. 

Thanks in advance!