This article is mis-leading. The NOLA streetcar system is not a well run transportation system.

I guess I should have said the initial quote's, lead sentence is misleading. However, it does set the tone for the rest of the article.
I think it's not an issue of engineering, but planning which as far as design elements go, is possibly more important than than engineering.  At it's inception in the 1830's it was most likely a viable route however now it serves only a small portion of the cities population and it's a portion that is not effected by bad traffic....not that NOLA has bad traffic by national standards.
But as far as the engineering of the system of NOLA is concerned one of the main problems was the frequency of stops, i.e. nearly every block along St. Charles, it makes for a very long commute! In addition, cars frequently blocked the street cars when crossing the tracks, leading to the lack of reliability.
Also, I think NOLA is a very different city than JAX, so it's very hard to answer your questions as a comparison between the two cites. But based on my experience with using multiple transportation systems, I can say this:
Modern streetcars vs. heritage streetcars? Doesn't matter
One-way loops vs. single bidirectional lines? In JAX I'd say bi-directional
Running in the same lanes as cars on Canal Street vs. running on their own dedicated ROW (medians)? I think this question requires a great amount of research and analysis of our city.

Hasn't it been posted here before that another way to cut streetcar infrastructure costs, is to have a single track with passing sidings at appropriate locations?  Until the frequency of streetcars reaches some critical point, this seems like a real money-saver to get the service on the ground.

Although a $1.5 billion pool of federal dollars earmarked for transportation projects is fueling optimism, securing the estimated $200 million total needed for the three proposed lines remains a daunting challenge. Work on the $161 million Canal Street line, which debuted in April 2004, spanned about 15 years from conception to completion.

The new proposals being considered by the RTA call for laying tracks along the North Rampart Street and St. Claude Avenue corridor, Loyola Avenue and Convention Center Boulevard.

The brightest prospect for financing is a component of President Barack Obama's stimulus package known as the Transportation Investment Generating Economic Recovery, or TIGER, grant program. Unlike traditional forms of federal aid that require local matches of as much as 50 percent, the $1.5 billion fund will pay 100 percent of the construction costs of selected projects. The application deadline is Sept. 15.

Because the RTA projects are already on the drawing boards, local officials think they might have an advantage over other transit agencies.

New Orleans back on track in calm after storm
June 12, 2009

The mayor says the city of jazz has got its rhythm back, writes Andrew West.

IN THE months after Hurricane Katrina devastated New Orleans in 2005, the city's mayor says the eeriest feeling was not the unusual quiet in the French Quarter, where jazz once reigned, but on Saint Charles Avenue.

For almost a year, the trams along the avenue - made famous by Tennessee Williams's play A Streetcar Named Desire - were off their tracks, destroyed by the hurricane.

"New Orleans has certain rhythms, and the streetcars are one of the rhythms. When they were not there, the city lost its rhythm," said the mayor, Ray Nagin. "Now you can hear that clankety-clank coming down the street again, and it gives people a sense that we're getting back to normal."

Mr Nagin is in Sydney to address a conference of the US Studies Centre at the University of Sydney, and last night took part in a City Talk discussion on climate change, presented by the City of Sydney and the Herald. He has become an enthusiastic advocate of public transport - and not simply for its aesthetic quality.

After Katrina, he said, the tram network would be vital for saving lives in future emergencies, especially in a city where almost 25 per cent of the residents had traditionally not owned cars. "We will have voluntary and, I hope, not too many mandatory evacuations almost every hurricane season," he said.

He is expanding the tram network with three new lines, including one to the Upper Ninth Ward, close to the area that was ground zero during Katrina. The trams will be linked to Union Station, where the interstate Amtrak trains arrive. "Our most efficient evacuation tool that we have in our arsenal is Amtrak trains," he said. "They move thousands of people out of the city very quickly. This was a lesson learned from Katrina. When Katrina hit, we did not have access to Amtrak but after Katrina we modified all our evacuation plans and now Amtrak is a critical part of it."

The city tested evacuation by train during last year's panic over Hurricane Gustav, which ultimately missed New Orleans.

He also wants to take advantage of the plan by the US President, Barack Obama, to build a high-speed rail line throughout the southern US to connect New Orleans to the job-rich corridor north to the Louisiana capital of Baton Rouge.

Mr Nagin has been widely criticised for the slow pace of rebuilding of New Orleans. But he insists that following "an event of biblical proportions", the city is ahead of the average recovery period of 10 years.

He said the population, including migrant workers, had returned to 80 per cent of its pre-Katrina level of about 500,000. Reconstruction work worth $20 billion had also created a booming economy.

More controversially, he has demolished every public housing estate in the city, aiming to disperse low-income housing throughout mixed-income areas.