I'd love an easy way to see which achievements I have left to complete, so I can set about working on them. If nothing else, it'd help me break out of my normal habits and take on challenges that I wouldn't normally explore. For example, I've done almost nothing with my test tube, but if I could easily see that there was an achievement relating to compounds, I'd be more likely to work on them. (I know there's the encyclopedia; I mean an easy way to compare what I've done with the whole list, to show what I haven't yet done.)