It is on my list to do ~ this year and I am getting close to it ~ but need more time! I got distracted a little in focusing on solar powered mining but now a node seems like a definite and logical next step...now that I have a available solar power to power it and all I need is the external data storage (via USB stick 2TB??)

Do not believe everyone needs to establish one but the more the better and for those who want higher level of security and participation in the protocol its a good step to take in conjunction with wallet security and home mining.

As you point out you need a fairly stable location and lifestyle to house the node...not everyone might have such a place to set up.