For speedy work flow in LR2 I import with minimal previews. This allows me to get to work immediately. Only when I want to see a particular image larger does it render a larger preview.

Then I quickly go through my images and find the rejects, flagging them as so with a stroke of the x key. Once I've flagged all the rejects, I can delete them all at once. I believe it's in the Image file menu, towards the bottom called Delete rejected photos.

Now I find my keepers, flagging them as "picks" by hitting the p key. If I need to choose between a group of images I'll use the compare or survey modes to find the winner.

It's also nice to make user presets for the develop module for settings that you use often. When it comes to sharpening, I find LR's own presets for landscape and portrait sharpening do an excellent job.