Thoughtful post, there.
Putin has billions, but keep in mind Ukraine's oil was massively subsidized....300-400 Billion will now be at Putins disposal should Ukraine go economically with the EU and not just politically, where it stands now. Additionally...Arab and Chinese investors in EU started to withdraw money and investments from EU as a result of sanctions...likely why also Obama is making rounds....needs to reassure nation leaders things will turn out "Alright"...tsk tsk... Sanctions are not the answer when so many nations are now "hardwired" through pipelines and International Trade deals at all levels. Which is why the EU and US used these...they knew it wouldn't do more than slap a few hands.....none were going to war over Ukraine....which is far more significant to Putin than the EU or the US.