Pardon any grammatical errors, I'm sure there are some it's when there should be its, or whatever. Trying to finish this quickly before the wife gets home so she doesn't call me a nerd.
Football - Louisville - Louisville's football's success in the early to mid 2000's paired with it's recent revival under Charlie Strong has to give Louisville the edge. Connecticut's only appearance in the BCS was abysmal and has been referred to by many as one of the worst BCS teams ever. Louisville's 2007 Orange Bowl win and success over the past 15 years gives the Cardinals the edge.
Men's Basketball - Tie - Both Connecticut and Louisville are perennial top programs. Connecticut has three national titles since 1999, most recently in 2011. Louisville's 9 final fours and 2 national titles catapult the Cardinals amongst the nation's top programs of all time. Both programs have been among the best in the Big East since the 2005 expansion. Louisville's basketball program was also rated the most valuable in the country by Forbes.
Other NCAA Sports - Connecticut - UConn brings national titles to the table in Women's Basketball, Men's Soccer and Women's Field Hockey. Louisville's overall athletic success is nothing to sneeze at as the Cardinals have found success in several sports including recent NCAA Runner-ups in Women's Basketball and Men's Soccer as well as a College World Series appearance. However, UConn's Women's basketball program is the biggest draw in college athletics outside of Football and Men's Basketball. The Huskies also have 5 College World Series appearances, however, none since 1979. Even though Connecticut has the edge, both athletic departments would be a well-rounded addition to the ACC given the departure of Maryland.
Replacing Maryland - Tie - If one is looking for a geographical comparison, then UConn takes the cake. However, in bringing in an athletic boost, Louisville wins this round. Football is King, and if the ACC is looking for the best all around competition, Louisville has the edge because of football. Connecticut's status in NCAA FBS (or I-A) is still in infancy. UConn didn't reach the pinnacle division of college football until 2000. While Louisville may not match up with the likes of Florida State, Clemson, Miami or Virginia Tech historically, it presents a much more viable option in the ACC remaining relevant on the college football scene. Also, Louisville's position in the Southeast fits in just fine with the ACC.
Television Market - Connecticut - This one is closer than one might think. However, UConn's residence in the densely packed Northeast gives the Huskies the edge. Louisville is not a small market, but it doesn't match up to the fact that UConn is practically a stones throw away from New York, Boston and Philidelphia. Don't forget that ESPN is also based out of Bristol, Connecticut. Certainly helps when looking at the broadcasting side of the argument.
Academics - Connecticut - Louisville has a larger endowment, but Connecticut is the state's flagship -- land, sea and space grant -- university. Louisville has phenomenal Business, Medical and Engineering programs. Connecticut is in the top 100 of several publications' top school lists, while Louisville is on the outside looking in. However, under the guidance of James Ramsey, Louisville has seen much recent academic improvement and success. While trying to look at this objectively, it's hard not to ask: Unless we're talking about an Ivy League school, the Big Ten or a handful of other schools (Stanford, Duke to name a few), is there really a difference? Honestly, both of these schools bring great and diverse academic aspects to the table.
Location - Louisville - Honestly, Louisville is a hidden gem. The home of Churchill Downs, the Louisville Slugger Museum, a scenic waterfront park and bars that stay open until 4 am is always a big draw. Seriously, I may be losing my objective view of this situation but there is a reason that Louisville draws several national conventions a year to the city and the aforementioned venues and upsides are just a few of the many great sides of Louisville. However, in 2005, Slate named Storrs the "Best place to avoid death due to a natural disaster."
Clout - Tie - Mitch McConnell is not a bad person to have on UofL's side. Many signs point to the Senate Minority Leader as almost singlehandedly engineering the upheaval in West Virginia's Big 12 bid last year. However, ESPN is the Nike to Connecticut's Oregon. It's fair to say that ESPN absolutely loves to see UConn succeed. Kemba Walker was a great player, but his legend was built by ESPN. Politics vs. Television... GO!
In all honesty, Connecticut is the better fit in many aspects of this argument, however, as I said earlier: Football is King. Louisville's football program may be just what the ACC needs at this point. Especially with the possibly departure of other ACC Football "powers" such as FSU and/or Clemson. While UConn may have the upper hand on many aspects, Louisville isn't so far behind that its status in football couldn't put Louisville into the lead position down the stretch.