It would depend on what type of clients you want to attract. Each area is unique. 

I am in a retirement/recreation destination area so my clients are pretty much retirees who have fled from the cities, small business owners, contractors and ranching/farming families.  I have very few young families and the only "college plans or UTMAs" are funded by grandparents.  If you want young professionals then an urban area would be where you want to go.  You definitely have more prospective clients in a city.

There are good and bad things about doing business in the town you grew up in or where people have known you for years.  It may be good if you have a sterling reputation and people who will do business with you because they have a level of trust that you don't get with a stranger.  On the other hand, they may still remember you as a young-punk pimpley faced teenager (I'm sure you weren't) and not be able to get over your youth.  

Pick the type of clients you think you want and the type of climate you want to live in. The recreational and social activities that you want to enjoy are important too.  If you like the theatre, dining on ethnic cuisine and doing the club scene, you would hate it here.  If you like to fish, hunt, golf, ski, watch sunsets and consider meat loaf an acceptable restaurant meal (I don't that's why I cook) then you probably would like it.

If I were just starting out, I would look for a place where, most importantly, I had a good firm or mentor in the firm to work with.  Lots of prospects to contact.  Contacts where your age isn't going to be such a hurdle. Affordable place to live (you won't have a lot of money in the first few years). An environment that I liked to live in.   You can always move.