I don't think that having an excerpt of the latest post is not a very useful information. Here's why:
Depending what was the last post that you read, knowing the beginning of the latest post is useless because you will need to go back anyway to continue reading where you left off.
Removing the excerpt would give back some space, and therefore show more content.
With the gained space, you could show how many pages there are for that thread, additionally to...