|Zach Klopfleisch Venture-Lieutenant, North Dakota—Fargo|
I always suggest at least a 12 CON and favored class bonus to HP for new players, with advice to go with 14 if at all possible. The added survivability tends to make those new player mistakes (like running into a double flank just to get a sneak attack because you won initiative) less lethal, but no less dramatic and worrisome. It won't guarantee your PC won't die, it does shift the odds a little bit more in your favor.
I consider going with less than 12 CON (14 for a front liner) to be an advanced technique. Play something basic but solid first, get an understanding of the game and get a feel for the difference that 2 or 4 CON might make, get to the point where you can walk away from a character death without feeling upset about it before you go tinkering with a lower CON. (Same thing with other advanced character building concepts like trying to create something from a movie, or trying to exploit an obscure or complicated mechanic from the Advice forums.)
I've GM'd 4 character deaths, I don't know about the one that took 20d6 falling damage, but the other three each had 10 or lower CON. The last one died to a surprise round shortbow crit with sneak attack, and two HP would have saved him.
3 of my characters have died, the one that died from HP damage had 16 CON and Toughness. But he took 120 damage at level 3 before he finally dropped, because the GM took pity on our party and pounded on him while he got healed MMO style to give the rest of the party a chance to whittle the enemy down. After I dropped, he proceeded to one shot KO or kill a party member per round until the Wizard finally finished it off with a wand of Magic Missiles. I chalk that up to a CON win, especially since the fight opened with a crit that would have killed my wife's PC outright which got redirected to my PC through Compel Hostility and didn't even knock him into single digits. (My other two PCs died to a Shadow and drowning.)
The classic MMORPG party is 1-3 DPS, a healer, and a tank. Those DPS characters are typically glass cannons. Glass cannons can be useful, but they need to understand their role behave responsibly.
Classic MMORPG PVE combats with a tank, healer, and DPS don't reflect Pathfinder combat well, though. Instead of the script + targeting algorithm of PVE, Pathfinder combat is against an intelligent, creative enemy who is trying to defeat your party, not just take out a single character.
This does, however, reflect a common area of MMOs: PVP. PVP in MMOs is a completely different game, and one of the universal constants of MMPORPG PVP is "Kill the healer first. Or the crowd controller." This maps directly to Pathfinder, even old school D&D. It's always a solid tactic to prioritize killing the characters that can either swing the odds in their team's favor (controller: wizard), or the character who can undo your actions (healer: cleric.) If you accept this, and work within the paradigm instead of trying to force an MMO PVE paradigm onto the game, things will go much more smoothly for all involved.