Plot Reset Tip! (Pattern Breaking)
Note that this is from my experience and results may or may not vary.
What you do:
Begin plot resetting as you normally would. For your first 4-6 (or so) attempts, be sure to press the power button, then the home button and relaunch the game (when you aren’t satisfied with a plot). You may have noticed that the villager plots tend to be in the same 2-3 (approximate) general areas. The above method (what I italicized) has a tendency to create this “pattern”. If this pattern doesn’t fit your needs, then breaking it is necessary.
To break the pattern, instead of pressing the power button then home button, completely power off your 3DS (when you aren’t satisfied with the plot). From here, you can continue to do the power button + home method (about 4-6 times again) because a new pattern has been created. If you are still unsatisfied with this new pattern, repeat these steps by breaking the pattern and testing out the new one.
Let’s say you’re a perfectionist and you’re trying to get a plot in the exact 3x3 area. If the pattern is placing the plot in the general area (close to where you want it to be), then continue using the power button + home method, and with enough luck/patience you might get it!
I hope this gave a bit more insight! ^-^b