Putin is doing everything 100% right (this article about invasion is total BS by the way). He is staying out of direct conflict, while supporting the rebels.
Explain how invading and annexing the Crimea is 'staying out of direct conflict'. Even Putin eventually got to the point where he couldn't deny they were Russian troops and keep a straight face, and admitted his Little Green Men were in fact Russian military. And explain how Russian troops, captured on Ukrainian soil http://www.bbc.co.uk/news/world-europe-28934213, are 'staying out of direct conflict'. Russia doesn't even deny they're Russian troops. And explain why NATO satellites have caught Russian artillery on Ukrainian soil http://www.bbc.co.uk/news/world-europe-28972878 and that's not 'direct conflict'. And last of all, explain how Russian SA-11 surface-to-air-missiles shooting down Ukrainian aircraft and a civilian airliner is 'staying out direct conflict'. A SAM battery is a complex system, not the kind of thing where you can just pick up the instruction manual, and they're typically operated by a team. How would a popular uprising find a trained crew for a SAM battery? The Ukrainian military doesn't even use the SA-11, so the only place to get a trained crew is from Russia.