GraphicConverter is great for replacing the paint module in AppleWorks. I switched to GC long before AppleWorks was even last updated.
There are a number of vector graphic apps around. Unfortunately, I can't find a list on iWork Tips & Tricks, but you might take a look through the various topics.
A search for vector on MacUpdate came up with these results. I did buy Sketch & DrawIt some time ago based on a recommendation by others, but haven't really used them.