This post is relevant to my interests! So much so, that I finally created an account to answer it. I teach at a SLAC, and love my job. I have no plans to retire early (although my husband does) because I like what I do so much. Whether it's the right path for you, though, is a more complicated question.
Some questions - first, I'm not clear on what you mean by having an opportunity available to you to do this in your hometown. Do you have a job offer on the table? If so, is it tenure-track? If you do have a concrete offer, then congratulations! Some of the rest of this post may not be relevant.
If not, however, I'd think seriously about the following:
What subject do you intend to teach? SLACS are less likely than other colleges to have nursing and/or specific 'pre-med' programs, because of the nature of the liberal arts mission. Our premed students major in biology, chemistry, or indeed in any one of a number of traditional disciplines. These programs are staffed by people with Ph.D.s in the relevant disciplines. MDs, whatever their other fabulous qualities, are not eligible candidates for jobs in these departments. I'm sure you will find SLACs with more specific preprofessional programs, and some of these might hire people with MDs rather than Ph.D.s, but this is not the standard model.
Also, do you have any kind of research agenda? Not all SLACs would require one, but the job market in most corners of academia (including biology and chemistry) is extremely competitive and getting more so. As a result, even the 'lower-ranking' SLACs increasingly expect an active research agenda of some sort from new hires, preferably one that allows undergrads to get involved. If you don't have publications and a track record of active research, you will not be a competitive candidate at many SLACs. Again, there will be exceptions, particularly down the prestige ladder (and those may be great places to work). But you would not be a realistic candidate for my 60ish-ranked SLAC, nor any of our peer institutions, without an active research agenda. And you would need to actually fulfill that agenda to get tenure; while it's not quite 'publish or perish' around here, we do not tenure people who haven't published at all since their hire. If you do have a job offer, be sure you are crystal-clear on what their research expectations are for tenure, and be honest with yourself about whether you are prepared to meet them.
If you do have a job offer on the table, I'd still advise considering the following caveats to your lovely picture of academic life:
1 - at least if you are at a place that expects any research, you shouldn't expect to have vacations free. I take a reasonable amount of vacation time, sure, but in general spring/fall breaks are for catching up on grading and summers are for getting my research done.
2 - I, and most of my peers, work more than 40 hours a week during term time. Achieving work/life balance is probably easier than it would be as a physician, but it's not a utopia in this regard. Don't underestimate the time that class prep, grading, committee work, advising, and other forms of out-of-classroom labor will require from you. Over time it gets easier as you get your basic courses well organized, but the first few years are a grind for most people, and even after that it's never the kind of job where you can leave work at work.
3 - if you do end up in administration, which generally does pay more, your job will almost certainly be year-round. You will be on contract and in your office through the summer, over breaks, etc. You'll get normal-person vacation time, but you will have much more fixed hours than professors do.
4 - Definitely make sure you aren't romanticizing academic culture. There are also "hollow shells of their former selves" in academia - and because they have tenure, they can hang around for a long long time! I love some of my colleagues and merely tolerate others, but the time spent in meetings to do curriculum review, run search committees, etc is certainly not my favorite part of the job.
5 - Similarly, many of our students are "healthy young people excited about life." But, especially if you are not teaching at Amherst or Williams, some of them are also going to be rich, entitled snots who expect their hefty tuition payments to buy them your undivided attention, and also an A; underprepared students from tragically bad high schools who need massive amounts of hand-holding to write a decent paragraph; and lackadaisical pot-heads who are mostly in college to get drunk/high/laid. I love working with students, but I definitely teach people who fall into all these categories. It's a lot of work, and sometimes frustrating, especially when students don't give a sh*t about their own education.
Anyway, I don't have much input on the financial side of things. If you are in a reasonable COL part of the country, you can make it work on an academic salary; because we are in a relatively remote location, most of my colleagues have spouses who stay at home or are minimally employed. They are fine, if not retiring early. But I would have a long, hard think about whether you have a realistic image of academic life, and whether you will enjoy the realities of that life enough to justify the financial trade-offs.
One final thing: on the MOOC/future of education issue - I'm pretty convinced that the top 100 or so SLACs will be find, because we provide an experience and level of personal attention that can't be replicated online. However, the marketplace is almost certainly going to get more competitive, and lower ranking tuition-dependent schools may be in trouble in the long run. For insight into these dynamics, you might poke around the archives of the blog Confessions of a Community College Dean (the author also has a book by the same name).
Good luck on your career decisions, and I'd be happy to answer any other questions you might have about SLAC life. There's also a wealth of knowledge in the forum at the Chronicle of Higher Education website - be forewarned, though, that folks there will pull no punches if they think you have a naive view of academic life.