Great question. In the last 12 months, we have undertaken a series of studies and experiments to see if we could reel back from our export-happy approach to provide customer reports. There is no real panacea here -- we have a legacy model construction that has been adapted (with expert help from the Apptio teams) for R12, where our original, implementation (project) team made decisions based on the tools that were available at the time (and wouldn't necessarily align neatly to eventual iterations of the ATUM model), which stymies the use of Master Data sets in some cases... and where Apptio struggles with providing intuitive avenues of "all in one view" data and graphs (which initiated the first forays into DW-based reporting), the exported/DW method means that change management efforts are multiplied by 2 or 3x (change tabular report, change export/import, change view elements in DW, update Tableau).
We constantly debate internally on where the dividing line ought to be between depth and breadth, as any healthy, growing team does.
Our long-term goal is to provide basic reporting capabilities that highlight actionable and objective intelligence on our IT Spend to the broader organization and use Tableau for supporting deeper, curated research that we intend to inspire the whole "Run IT like a Business" mindset. The Apptio "Out of the Box" solutions, which tie to ATUM constructs and should meet expectations for 80% of the TBM user base, are very close to being broadly deployed (nearest target is Aug 2019) to coincide with a significant modification to our cost model which aims to move us from nearly pure 'cost transparency' only to 'showback and cost transparency' views.
I hope this helps. I'm a pragmatist in the end -- whatever it takes to create the opportunity for victory in the space we can influence … but I also don't want to kill our flexibility in the long term, so we continue the good debate and search for a virtuous cycle with all our toolsets...