israel is occupying palestinian land as a fair result of war, whether the palestinians declare a state or not. A right to your land flows from the legal requirements of "attachment" to "you country". Both Jews and Palestianins fulfill those requirements. Now, you may be right that this may spark a regional war, because it further polarizes the current political situation, but declaring an independent state does not give Palestinians only "rights" of a sovereign state, it also forces them to comply with significant obligations. Also, whether they are mature enough can only be answered by looking at what they do as a state. The requirements of a state actor are not very different from what they have been required to do up to now, they still have to have governance, diplomacy, representaion and compliance with international law. I am totally in favor of a declaration as a state and I do not feel Israel has anything to worry about "procedurally" speaking.
Israeli troops shoot, injure Palestinian crossing Gaza border fence (Haaretz)
from the article: Abbas: Only solution is to declare Palestinian state