1. I would've reset longer. I actually spent June 9 resetting, which was tough for me to do, after waiting so long and knowing that so many others were already enjoying the game. On June 10 I settled on a town that had the features I was looking for (certain building placements, triangle grass, apples), but it's not 100% flawless. The river, ponds, and rocks could be better... I kind of wish I was pickier so that I wouldn't have those slight lingering regrets. What if I reset a few more days and found a better town? :/ I couldn't reset my town at this point, but I'm thinking of starting up a second town to see if I can find the perfect layout and such.
2. I would've put my house one space lower than it is, so I could fit a row of trees behind it (Not a big deal, though

)
3. I would've done the choose-your-villagers'-house-location trick! >_< By the time I found the thread about it on here, I think I'd already gotten 9 villagers, pretty much all of them in bad locations. Now it's a waiting game for them to move out (I don't TT so it could be a while).
I haven't built permanent projects like the caf?, campsite, police station, etc., so I don't have anything to regret there (yet). The caf? is the main one I'm thinking about building right now, not too interested in the others.