This was posted a while back. Worth watching.
Whilst I do agree a deal needs to be done, even if the politicians agreed to allow Russia to completely take over Ukraine, the people themselves wouldn't accept it and would keep fighting.
Crimea and the Donbas region - and I guess all of the Black Sea region could be given up to save the rest of the country. Recognise the Donesk and Luhansk republics, Ukraine backs off from joining NATO, Russia accepts "Western Ukraine" seeks closer ties with the EU, everyone agrees that any further incursion by Russia will result in the same outcome as we have now (but with a stronger Ukraine defence force), internationally run humanitarian aid for those in the new republics (if required) but safe passage for those that do not want to stay in those regions.