Maybe that's not a terrible result, but what if dude is average to solid otherwise, but has a 3 luck and gets Bountiful harvest. Yay, 1hp/level forever? That's not going to last long, no matter what the AC.
Otoh, that character is *extremely* rare. First you have to roll a "3" for a stat (about 3% chance), and then for the Luck stat in particular (1/6 chance, cumulatively about .5% chance ), and then the auger for HP (1/30 chance, cumulatively about .015%). So out of 10,000 randomly generated characters, you'd end up with the poor fellow in question (1hp/level), but you'd also come across his uber-lucky cousin with +3hp/level...
Yeah, but even a more likely result of -1 or -2 is still potentially crippling, combined with the randomness of the HD rolls.
I liked what people were saying above about making the Birth Augur just a flat +1. I think I'm going to do that.
That's cool, I'm confident you know what's best for your group, and that's all that matters of course!
Some of this is just framing and perception, and has much, much less bearing on character viability/survivability than the thousands of happenstances that make up the character's life. Over a theoretical 20 session arc that takes a party from 1st to 3rd level, there will be only three rolls for HP. Regardless of the Birth Auger, it is entirely conceivable that Al the warrior rolls 8, 4, 9 (not bad!) whereas Bob the warrior rolls 3, 6, 2 (ouch!).
Please don't take this as an argument; I'm more just spitballing some observations! My favorite characters have sometimes been the "crippled" characters that manage to survive and ultimately flourish, if it isn't clear from my advocacy.