brewing

Sounds like your goal is to create a startup. If that's your goal, why are you getting a PhD?

If you are still looking for a funded French masters for next year, consider Miami OH:  https://www.miamioh.edu/graduate-school/admission/index.html
What matters is that it's free! They also have great placements in top PhD programs in French.

Unless you are independently wealthy, do not do that. You will absolutely be a second-class citizen in the department, and you will never be a professor's first choice to help with their research. In offering you admission to the MA program rather than the PhD, faculty members in the department have clearly stated that already. It would actually make more sense to go to UW Madison, gain some teaching experience, and master out after two years while applying for other PhD programs during year 2.

In my case, it's because there's a professor at Stanford I want to work with—and I actually think I can help with her research

It really comes down to whether they can be honest with me about it or not.
Hopefully my seminar papers and publications will be better than the actual PhD students' 

Given that this MA program is brand new, it seems to me Stanford is trying it out to increase funding. The idea would be to have a few MA students every year to support PhD stipends. What is Stanford's tuition? $70k? That's the stipend for two PhD students that year (the tuition for PhD students is basically imaginary). Other years, students will teach and what not, which will draw from the university's teaching fund. It won't even out exactly, but it will heavily cushion the French department's finances, which has been in serious trouble, along with the entire DLCL. I personally wouldn't want to be a second-class citizen in the department.
Doing an unfunded masters will not work against you, but it will also not impress faculty. If I were you, I'd look for funded masters programs in French. When such programs exist, it makes little sense to pay $100k each year (tuition + living costs) to get a masters degree in French from Stanford. Sure, it's a big name, but it's quite easy these days to get into big name schools like UPenn and Columbia, which have so many cash-cow MA programs that trade the uni's name for cashflow. If this degree was one with heavy payoffs (like CS!), we could argue that it makes sense to do it. 
(Btw: people do not get paid $15k speaker fees haha—at MOST $1-2k + travel and housing costs is typical! I've even organized to pay $500 speaker fees to a tenured Ivy League prof.) 

OMG please no—do NOT do an unfunded masters in French. It's money down the drain—unless you have lots of it, then up to you. I'm surprised that Stanford has this new path, but it makes sense, since they are short on $$ these days. In this regard, you would just be funding their PhD program.
The reason people do not graduate in 5-6 years is not because they can't. I could have rushed my dissertation and finished it as a fourth year. No, the time-to-degree is long mainly because people try to spend as much time as possible collecting teaching experience and applying to jobs. There are barely any jobs, and 5th year PhDs rarely, if ever, get those jobs. As someone at a school where the teaching load is relatively low, I can guarantee you that having less time to teach does not make me—or any of my peers—more 'productive' in our writing. It actually works against us, since most jobs are teaching jobs. 
The longer time also allows us to think about how to transit out of academia. The majority of French PhDs, even from top programs, will not find tenure-track jobs. It's not easy to just wake up and switch—it takes some work. Spending as much time as possible reading and writing things we care about is the only true romanticized outcome of French PhD programs. Not everyone can afford such a lifestyle, esp. if they have kids, loans, other issues, etc.
 

Hi ! Finally something I can answer, I think. To be honest, as a French person, when I have been called "tu" by a Professor, I generally only adress them as "vous" anyway (because they are your superior they can call you "tu", but because you are a humble student it is preferable to use "vous"). In my opinion, I would only use "vous", even when being adressed "tu". It avoids sounding too familiar. 

Hi ! I have also received a similar email by the same University. I too was a bit confused by the "recommended for admission" (what is that supposed to mean?). I politely turned down their offer because I was made an offer by UVA, hopefully that might help if you're interested in the program ? 
To be honest, I applied there without knowing to much about the French Department... I have read online that their French Program is pretty good, but yes, I have also been told here that the funding is meh. 
Sorry for not being more helpful... 

Hi guys !
I have received last Saturday an email from UVA's DGS informing me that they had accepted my application. I am very excited. I do not know whether they are going to accept other PhD students this academic year, but if they do please feel free to send me a private message, I'd love to know who else was accepted and with whom I will have the opportunity to study.
Best of luck to everyone

I'm not a total expert, but I would say:
Keeping your answers as brief as possible always allows more time and is reasonable considering how brief the interview is. Don't ramble the time away. 
In your answers, you can leave things open ended to provoke a question on their end for you to talk about what you left open ended. Lead them into the topics you want to discuss or highlight. 
They have an agenda of questions to get through, which you can't control. They usually leave 5 minutes at the end for questions which isn't much. So when you answer their questions, you might bring up something in your answer that could spark them to think of something to tell you that you would have wanted to ask as a question otherwise. 
Being prepared as much as possible beforehand - polishing answers to prevent yourself from rambling. Also, preparing all the questions you want to know from them so they're clear in your mind and written down for you to reference.
I hope this all makes sense. Again, these are my ideas based on my experiences with these 20 to 30 minute interviews.
*edit - I also, have written down every question asked from all my interviews - which helped me prepare for the subsequent interviews.

I also cannot believe that these interviews seem to be extremely short. The Stanford panel interview seems to be 20 minutes. 

Does anyone have advice on how to structure the interview, and influence the topics (because clearly we cannot be comprehensive in this amount of time)?