Personally I would forget about suspension - the bike is already going to weigh proportionally much more of her weight so will be harder work. Most kids really don't need suspension too much. Saving a kilo or so will be much more useful.
Look for shorter cranks - the biggest fit problem is over-articulating the knee, which also reduces pedalling ability. It's like us trying to pedal 250mm cranks. Spa Cycles do some reasonably-priced 150 or 160mm chainsets, and they come up occasionally on ebay.
For braking, make sure you use the lever reach adjuster to get the lever closer to the bars, which should of course be less wide.
Islabikes are good examples of how a good kids bike is set up. My 9 year old overtook two blokes on carbon full sussers on his rigid Isla 24er the other week.
Ride it or milk it!