Taking skills and my experience in Kingmaker into account you really need to completely focus entirely on a very few skills if you hope to succeed. I keep seeing target numbers of 25+ being thrown out by the DM. With our level 6 characters we really have to have focused on a class skill or have some related stat that provides pluses here. My cleric is very sporadic with his knowledge Religion skill which is maxed out. I really would have set myself up for failure if I had put skill points elsewhere trying to present a background of skills for my character. This is a problem for me.
My Cleric has a background of someone who has traveled a bit. I would like to have skills that represent basic knowledge of places and geography. But under the pathfinder and therefore D&D system I really can't do that. I need to drop my skill points in a small set of skills if any are going to succeed. I don't want to use these skills for a one of knowledge check for some particular history but rather just a general customs knowledge and some broad navigation skills. This is easy enough to tackle in a skill based game, but becomes a point of difficulty in a level based game like many of the traditional fantasy rpg's.
The difficulty becomes elevated when you get into a skills arms race situation like in D&D pathfinder. character create characters with splashes of a class which allows them to perform as well as a character with the full class in a subset of skills. Then you have the DM ramping up skill checks to challenge the party. Throwing a splash of ranger for tracking on a rogue or bard is a common example of this. The bard now gains a useful skill for their extra skill points and perhaps some extra combat power, so its a pretty big win for them. Now you the DM have a more capable party to deal with and hit them with elevating challenges.
I think the Rolemaster system is the only one I have seen that really does a good job of tackling this problem. Skills have en exponential coast so it just becomes unwise to skill up beyond a particular point. Mathematically you are driven to diversify.