I think the skill-system has been improved with Pathfinder comparing wit 3.5. But one thing is problematic in my opinion: class-skills only make a little difference. But class-skills should be a way to make classes different to each other. If the fighter can disable devices nearly as good as the rogue that feels a little strange.
That's why I think about a house rule for my campaign, to increase the bonus from class-skill about one point for every 5 ranks put into the skill (+3 for 1 rank put into the skill, +4 for 5 ranks, +5 for 10 ranks etc.).
What do you think about that?