Dude, get her a newer blaster with hydraulic disk brakes, they're a little harder to find and a little more expensive, but definitely worth it.
Those crappy bicycle brakes will wear out her hands pretty quick, they're hard to keep adjusted right, and there's no way to take out all the slack.
There are conversions for older blasters, and you can even retrofit banshee brakes to the blaster, but it gets expensive real quick.
Other than that, banshee shocks on the front with the widest a-arms you can find, 250R shock on the rear, banshee axle for +3 width, LT250 carb, and a shearer pipe.
Total for all that stuff on my wife's blaster was extremely cheap compared to doing the same stuff on a 250 or 500, and it made a huge difference...not even the same bike I started out with.
There's a lot more you can do to the engine for more power, but the 250 carb and the shearer pipe made the powerband a lot more consistent and easy to ride.