I've voiced my love for limited level progression a few times in this blog. Often revolving around Epic 6. If you don't know what it is check it out. Epic 6
I love the epic feel of these campaigns. To me a limited range of levels keeps the game grounded, no power or epic levels where players become superheroes in fantasy. Limiting hit die and attack bonus means there the game stays closer to most fantasy fiction.
Without the hundred or so hit points the players are never able to just waltz in and slay a dragon. Dragons and other high HD creatures will always be Epic and scary.
Limited level games make the need and necessity of epic weapons and armor quest worthy. Want to take out a dragon? Sounds like a quest for Dragon bane swords and resistant armor is in order. Rings of power and sound tactics. Anything less is suicide.
My house rules for starting hit points to be equal to constition score plus level grew out of my epic 6 games. (often with a small bonus for fighters and clerics. Or racial bonuses)