Hi Rich. There are a lot of factors as to why you may be experiencing poor signal strength from your E2500. There may be a lot of wireless interferences in your area (other wifi or wireless devices) reason why you should try isolating the issue by changing the channels of your 2.4ghz band testing channels 1,3,6,9 or 11. You may also try strategically relocating your router at the middle of your place avoiding thick or brick walls and giving consideration to the distance of your connecting wireless devices to your router.
You may also refer to these KB articles if you need further help with your E2500:
Getting poor or no signal from a wireless router http://www6.nohold.net/Cisco2/ukp.aspx?pid=80&vw=1&articleid=3759
Extending the range of your wireless network using the Linksys RE1000 http://www6.nohold.net/Cisco2/ukp.aspx?pid=80&vw=1&articleid=25636
We would suggest that you also get a Linksys RE1000 which is configured to work best with N routers like what you currently have. Read more about the RE1000 here.