[dwmintz]

I'm a huge proponent of the idea of centralizing the data model. That's the core idea behind Looker (where I just came to work after 3 years as a customer), and I agree it's a hugely powerful change from the world of everybody-in-their-own spreadsheet.

On your other point, though, to echo the build vs. buy discussion from above, I think it's a bit misleading to say "oh, we'll just use an open-source solution and that'll be cheaper." Because if open source means a couple of internal developers and an analyst, that's easily $300k+/year in salaries that you might not spend if you were using a vendor.

Anyway, given your particular statement of the problem you're facing, I'd humbly suggest you take a look at Looker. The data modeling layer that's core to Looker is meant to solve EXACTLY that problem, by leaving your data where it lives and then embedding your business logic in the layer that sits between end users and the data.