5000 words on one page is, to me, too much so it's a good thing that you are shortening it.
1000 words should be enough to write the informative content you need, with the appropriate keyword content What I wouldn't do is try and talk about too many things whilst sticking to a stringent word limit. Rather than that seperate them out into seperate pages as you see relevant. That way your content will still be relevant, good and focussed.
Something to think about regarding effects on page rankings. If you cull your content too much, so much so that it is no longer good content, then I could see this affecting your bounce rate significantly. Be careful about over do-ing it, but I would much rather see a page with 1000 words of content than 5000.
It would be the knock on effects of shortening your text I would look at, rather that the sole issue of 'less text'.
Danny