There is a lot of work to be done on flags, emblems, language, holidays, political structures, services and tax.
In that order (not necessarily order or importance):
What will the Irish flag be?
What will the anthem be and in what language?
How will unionism/Protestantism be reflected in the symbols of state and government?
Will 12th of July be a public holiday in part/all/none of Ireland?
Would Ireland be in the commonwealth?
What role for British monarchy?
Would some/all/none of Ireland have a public holiday on days that reflected British identity (e.g. monarch’s funeral)?
Any recognition of Ulster scotch (I know)?
Would Ireland be a 32 county unitary state?
Or would there still be a NI with power sharing?
Would there be equivalent devolution elsewhere?
As signatories to the GFA what demands will the London government make?
How will they be petitioned by unionism?
What would the policing status of NI be and what resources would be in place if there was an upsurge in violence?
What would the trading agreement be with GB?
What would the EU view on that be?
Will the public services be the same in NI as in RoI currently? If so would be people have to pay for anything that is currently free? If it’s not the same will RoI taxpayers have to pay for any service that they won’t receive?
What will the divorce settlement with GB be in terms of assets, debts, future liabilities (pensions being an obvious one)?
A lot to work on. Pointless demanding SF or anyone answer all of them overnight but they will have to answer some and show that they are progressing the others. Ultimately they will all have to be answered.