The D3200 is a pretty good camera(but tiny)... especially if your use to a D3100's clunky interface. If you want something to grow into, I would really suggest getting a used D7000(I have one) for nearly the same price as a D3200.

If you're interested in a gripped D3100 for an excellent price, I have one that is lightly used and want to sell it along with my 18-200VRII.I haven't touched either in a few years and since I'm about to drop some cash on a 24-70 2.8 for my D600..... I gotta sell em.

For what it costs now, it's an amazing camera.  My wife has had one since about March or April or whenever it was they first came out, and she loves it.

I've played with it a couple of times myself, and it is rather impressive.

There's another thread recently about this same issue where the OP went with a D3200 so you may want to search for that.

A few quick summary thoughts:
1.  Lots of great cameras out there.  You aren't looking for the best camera.  Or the camera with the best specs.  Or the best camera you can afford.  You're looking for the camera that does what you want it to do and fits your needs.
2.  D3200 has lots of positives.  A couple of things that rarely get mentioned but are big motivators for some who go with it:  it doesn't have an internal AF motor in the body (both a pro and a con).  But on the positive side, that makes it smaller and lighter.  If you've got small hands, little fingers, have any kind of shake (my Dad for instance has early Parkinson's), or it's just difficult to hold a big body for a long shoot, than a smaller-lighter body is a huge plus.  And that's the D3200.
3.  This is one of those deals (if you feel comfortable with the D3200) where you want to go to a camera story and hold two different bodies.  For comparison (b/c they'll have some similar setup), hold a d3200 and a different Nikon (like a D90 or a d7000 or D300S) and you'll notice the size/weight difference.  And you'll be able to see if you actually like a bigger camera (I have stubby fingers and actually prefer a bigger body).
4.  Remember, D3200 has no AF motor.  So you either acquire lens that have an internal AF motor in them.  Or you shoot all manual.  That's not necessarily a negative, you just need to be aware of that in making your decision.

One last thought (that may be completely irrelevant to you).  Smaller cameras tend to be less intimidating to some groups of people when shooting overseas.  If you travel a lot, especially to LDCs and shoot, a D3200 with a smaller lens is generally going to get more smiles and cooperation from locals in rural areas.

Ed

+1  I absolutely love my OMD E-M5.  The 45 1.8 is an amazing lens and combined with the OMD it continues to blow me away.  If you can find one used you can pick one up for about $300,  but $399 for this lens is still a bargain.  I'd strongly suggest the grip, but with so many after market grips just the one piece is perfect to make this camera complete.  If you want a capable camera that you can still grow into with a ton of nice features. Check one out.

They were going for $200 under normal price on black Friday here im Canada so I got an om-d and have to say I'm loving it so far! Tiny, light and great image quality.

...and you know, for portrait shooting, a lot of manual buttons and switches aren't really that big a deal.  It's no biggie to hit the "info" button and make a few quick changes on the LCD for a series of images.

People spend way too much money and time on gear they usually don't need to accomplish what they're trying to do.

OP, I would just get the D3200 and buy some quality lenses.  You'll have the glass for years.  The camera will be obsolete in a year and a half.  You'll be glad you didn't pay $3,000.00 for it.

Praktica MTL 5 B - came with 50mm 1.8 in the kit and a flash (sadly, the flash no longer works due to having batteries left in it while stored) Can often be found in charity shops for approx £5. There's also masses of m42 glass available on ebay for pennies to go with the body......

This isn't a facetious answer, in case you're wondering. Being limited to 24 or 36 frames per roll slows you down and makes you think about what you're capturing; especially when you're paying for processing at a lab rather than doing your own printing.

I'm looking up at the shelf where mine is sitting and wondering if I can get hold of some film today to capture the weather.........

I can remember wanting one of those so bad - but it was out of my price range and I had to settle for a zenith instead. I so wanted the east German technology over the Russian.