Stability won't really come into play much.
I guess you don't use a lot of animals (improved Trip feat), Monks (Trip, Bull Rush) or Tanks (Bull Rush) in your game either?
And if "low center of gravity" is the excuse, then why doesn't the Halfling or Gnome (or Goblin) have the bonus? They are just as low to the ground as dwarves.
Movement -- everyone looks at this and says "we've given too much to dwarves!". Look at it this way: they're Medium-sized creatures (and were in 3.0, too), who are handicapped by having a maximum 20' move in light armor (but are the same as other medium creatures, otherwise). It's a penalty, not a benefit.
In other words they are small creatures without the size modifiers? Sorry, I'm not playing a violin in sympathy for dwarves. Again, if "ability to carry weight" is the argument, then why do Orcs and Half-orcs have the penalty? They are described as being able to carry such loads (wide shoulders, haunched backs, etc).
If you want to play around with the Dwarf and give them these sorts of benefits be my guest, but make them pay for it in other ways to balance them - give them a LA/ECL+1 or better yet give them "Light Sensitivity" - they spend their whole lives underground, they have Darkvision (not low-light), why not the -1 penalty in bright daylight?