First, forgive me. I am writing this short post from my tablet. Its been a long rough day at work so I figured I would calm my nerves by sharing a tip I have for you GMs out there.
In the past when I actually planned long campaigns, what I would do is run several short term, one shot games as I try and get a flavor on what works and what doesnt in my what I call "My Rough Draft". So, I create a pile of Pregens for my players to choose from, and let them go wild. Each time they play a game they could pick the same character or pick a new one and try something else. Usually, over a course of 2 or 3 games, some players get conected to a particular character. Which is good.
When it comes time for the campaign to start, players create there own characters and head out in the world. Ok, so what? Well you have a pile of pregens not being used. Well, they all become NPCs with back stories, that have been technically written by your players. Playing these NPCs in the same manner as they were played by their previous owners, using the past games as the actual history of these characters instantly creates a bond between them and your players. So when witnessing the death of this NPC, or being betrayed by one of them makes the sting even more tangible
And that is how I get players to feel for their NPC friends a little more. Maybe others do this, but id thought I would share.