After getting a standard user set up (so I'm not directly touching the admin account), the first step is to set up a new Power Platform environment to keep all the development tables and apps away from the default instance. I'm also tempted to have a Dev / Test / Prod environment too. Yep, may as well go full lifecyccle management from the get-go (It'll be in Dev for a significant chunk of time anyway).
Hmm, apparently the tenant doesn't have enough space for the database. Sure enough, database capacity is 0 of 0, No space allocated. Might see if I can create the environment without the dataverse database and make afterwards. Hmm nope, still complaining about capacity constraints. Tried signing up for the developer plan for power apps, but it just took me to the same environment. Looks like Microsoft confirms that the developer plan cannot create environments. Oh well.
The next alternative is to create separate databases in the dataverse of the default instance and hopefully link them to separate solutions. Actually without environments the standard solution export / import isn't going to work. Possibly just use DevOps and branching?
Setting up DevOps it looks like my personal account had got there first to register VRBones. Since my personal account is also set up as a developer for Visual Studio, it probably makes sense to leave it there, so I just added the organisation admin and standard user to the mix and made a new TournamentCompare project.
Upon looking into the DevOps integration it looks to be only with VS Team Services account. Ok, it looks like I'll just need to build out the app in default and keep it lightweight before deciding whether lifecycle management will help to push out anything.
Tournament Template files created pretty quickly. Next step is to check the model-driven app and especially the self-referenced heirarchy.