Answers

As a roofing contractor, of course I am going to suggest an upgrade to your roofing system. And that's not just a biased opinion either. Working with a lot of realtors in our area it has been proven that the roof can be as much as 40% of your curb appeal. Especially when the system incudes things like the right color drip edge on the rakes and eaves, and high profile ridge caps. Both of those items are relatively inexpensive and can make a very noticibale difference compared to homes that don't have them. Selecting the proper type of shingle of course also plays a huge role. About 95% of re-roofs these days use a standard architectural tpye compositions shingle but picking something from the designer line can realy make your home stand apart. Then again, other rof covering options besides ashphalt shingles can make an even greater impact. 

As a GAF Master Elite Copntractor, we are partial to their line of products and I have included a link below to their designer apshpalt series.

Good luck!

http://www.gaf.com/Roofing/Residential/Products/Shingles/Designer