With a $5k budget, there are almost limitless choices of really good bikes. I would suggest going and test riding ones and comparing major differences, such as endurance vs. racing geometries, shifting; electronic vs. mechanical, etc. Think about the roads you'll ride on, and how you'll use the bike and choose accordingly. Since you've ridden in the past, i suspect you'll quickly narrow down at least what style bike you want and major features.

Trek, Specialized, and Cannondale all have various types of active suspension, which is nice for really poor pavement and I would recommend riding one or more of those if you think it may be beneficial on the roads you'll be riding. Roads in my area are abysmal and I really appreciate the Specialized Future shock system, especially on long rides.

Another consideration is maintenance. If you do your own, you want something you feel comfortable working on. If you will use a shop, you may want to focus on brands that are carried by shops you are comfortable with.

Good luck with the search. Make sure to post pics when you get one.