Things in Ukraine have become out of control. The separatists are able to inflict more damage than they would if Russia was not backing the separtists. I whole-heartedly believe people have the right to govern themselves, but they should earn it through diplomacy, not conflict. Now that other countries citizens have been harmed, Russia needs to pay or back down.
The fact that they could shoot down a commercial flight and claim it was an accident is inexcusable. There needs to be better control on who is calling the shots for defence. Clearly that was not a plane that would bomb the country. Many innocent lives were taken and that needs to be addressed.
I know that this will probably hurt their economy and the world economy as a whole, but I think that someone needs to show Putin that this type of thing will not be tolerate. Clearly he is on a massive power trip and we need to make him tone it down. He cannot kill innocent civilians.
Essentially, there isn't any point in imposing further sanctions on Russia as a knee-jerk reaction. Too many European countries would refuse to co-operate as they depend on Russia for things like their gas, which they can't do without. Unfortunately, Russia knows this and will take advantage of it. The rest of the world may have to be more creative in their dealings with Russia than simple sanctions.