My view is that they chose ETH for a specific reason in a year time. ETH is still minable, therefore less likely affected by big dumps (during the year token process), so to invest in transparency as a marketing label, for me is just a way to do strategy. Something is not being said. And I believe that selling ETH from an ICO will become a much more profitable choice than BTS for whoever has BTS by then. Then put something like a contract to allow BTS and STEEM to participate over EOS expenditure, and you boom BTS again (STEEM along... with it..).
But I could be wrong.