OT: What is the most marketable degree at LSA that's also not super intense?

This is going to be an individual that has a mid life crisis.

Tell him to find something he IS passionate about, and not what he thinks will land him a job.

As someone that transferred from LSA into engineering I have a bit of experience with this. My first question is what is his GPA? I know that back in the 90s at least the minimum GPA for even IOE was a 3.0.

Also, and this might sound obvious, but such a move will surely set him back a semester or two. I actually took a big risk by taking ME classes before I even got into engineering school to lessen the blow. Luckily I got in so those classes weren't wasted.

I would recommend him scheduling some time to speak with a Career Advisor at the University Career Center or engage the LSA Opportunity Hub. They would be able to speak with him on a personal level to understand what might work best for him. My wife has worked at the UCC and works for the Hub, both are great resources for students that some don't realize.

Yikes, sounds like a rough situation.

As others have mentioned, communications can be a road to HR, PR, and other similar corporate-type positions.  But based on the skill set described ("not very outgoing" "intimidated") that might not be an ideal fit.

Other LSA-based options could be ones that seem to me at encourage those less: econ, stats, biology, chemistry, etc. Of course, someone with one of those degrees might say that I'd dead wrong on that, and what do I know with this history degree?

I don't think Ross/CS/Eng would be appropriate given what you've described as the struggles. It seems that would only make the situation worse given how competitive they can be.

I don't know, but the MACC program used to be very competitive. I mean accounting itself is super easy, but it used to be graded on a curve and Ross kids are smart/ study hard. I don't think it would be a problem to have a B- average in accounting and still get a good job, it just won't be for the Big 4.

I got a political science degree there, decided not to pursue law school, and made a career in marketing/advertising. Political science has "science" in the name but doesn't really require any :)

This one is curious to me, given the whole point of LSA.  The whole process of a liberal arts education is about the journey, not the end result.  Heck, they tout that right on the LSA webpage: "In LSA, answers aren't always the end goal." It's about the process and what your family member is experiencing is completely normal.  The problem, though, for the student with uncertainty is that they are surrounded by students who vocalize that they know exactly what they are going to do (hint: they don't, it's mostly projection) and it becomes an echo chamber (because the students who don't know what they want to do don't vocalize that) that has incredibly deleterious psychological consequences, that are particularly pronounced among first generation students.  Often times I find that one of the most impactful messages to convey in situations like this is just "it's ok. It's ok that you don't know what you want to do yet.  Go and explore."  It's important to not get boxed in when you don't know what to do, thus LSA touts (which is true): "In LSA, you don't just train for a vocation" and "the power of a liberal arts education is that it's infinitely adaptable".

Not history, there is no future with that degree literally or figuratively. 

I don't know how close your description of the student is to reality (I presume it is at least a few degrees off, since it reads as a rigid, unhappy, low-ambition caricature), but even if it's fully accurate, I'm skeptical that a thread like this will be of use to someone the posters have never met. I think it would be better to motivate the student into believing he can find a perfect fit, rather than settling for a proposed paycheck he finds acceptable. Here, the best advice is usually too old and obvious to not be trite but true: 

- Take the thing you love more than anything and become so good at it that a sufficiently large fraction of the world calls it valuable (that is undergrad concentration-independent)

- Alternatively, I think undergrad is the right time to shop around and do so with zero sense that it is even possible to be wasting time in irrelevant courses. Stop caring about the time.

This can be especially hard and valuable for 1st generation college students. I should know. I was one and it was hard for me. Roughly 2.5 years into undergrad, my GPA languished around 2.3. For a kid who had been in the top 3 of his high school class, that was hard to accept or understand. But not impossible. I just fucked around and partied too much. Never went to the library. And put minimal effort into every class. I fully deserved that grade.

But I didn't give up on my big dreams (medical school, believe it or not) or self-worth and won some sort of luck jackpot when I stumbled into intro biochemistry (Ursula Jakob). That course changed my life. Suddenly, I had a means to develop realistic hypotheses for any of the weird biological and medical questions I had. That background was a real power. And I had an apparent talent for it. Eventually finishing with a double in (a) C.M.B. and (b) Polisci. Lucky for my future, I absolutely killed it my final 2 years and raised that GPA to the 3.2 range. Typically that would be far below what is expect for medical school, but I matriculated as an MD/PhD student anyway and am now one year from securing both degrees. 

This may come off as shameless self-promotion. Though not my intent, I admit that is tacky and hopefully you guys will forgive me as telling this story without that part is hard to avoid. The real moral for me was this: Everyone can be best in the world at something. And if Michigan accepted you, the odds are in your favor that your something is a worthy one. But that doesn't guarantee that you'll find this thing of yours. I found mine the boring way - introspection and a refusal to quit.

I think that might be the best and most realistic prescription for the student described in the OP as well.

Find a non-Spanish language to major in. You’re living in a highly mono-lingual country where companies kill for someone who knows how to fluently speak another language that isn’t Spanish.

I know this is far easier said than done, but if someone can be fluent in Mandarin, Arabic, Korean, German, or Japanese, it almost doesn’t matter what their level of business acumen is coming out of college. They will get hired, and they’ll get paid great money too.

Michigan is the kind of place where you have to be self-directed and self-motivated or you'll fall through the cracks. If you're not, I would imagine it must be very stressful, especially seeing other kids who seem to know exactly what they want and are actively pursuing it. I was a Communications major. It was media-driven back then, with classes in journalism (my concentration), mass media, freedom of the press, and also organizational behavior and communication. I went into advertising as a copywriter. One of my housemates went to work for the Brooklyn Academy of Music and then the World Wildlife Fund, in a PR capacity. Barb McQuade was in my class (she was the sports editor of The Daily back then), and she's now an attorney (no politics, but she was appointed by Obama as a U.S. attorney in Michigan) and law professor at Michigan. Lots of options with a communications major. 

I would find him a path to any reasonably respectable degree, but have him work as many internships as possible in whatever area(s) he has interest in career-wise. Even if he takes any extra year to graduate.