Did you work in a team?
Three members.
Programmer - MillsGameDev
Art- CobbKobu
Maps - Tom Neal
We really had a good time. Really blown away by CobbKobu's pixel art. Tom was time limited but help immensely with maps.

Was the resolution a challenge?
With the art style the resolution was good. The limited screen size makes the game harder (you can just walk by someone without noticing).
Making text work was a big issue. The game needs to walk the player through the story and that takes a lot of text. With the original font it was just too many screens. Had to write custom text screen since unity's built in text UI object was bouncing as the player moved. Used a very tiny font which makes the letters like m and w hard to read but reduced the screen count a great deal.
I spent a good two days trying to track down a memory leak. The game worked fine while developing but when we throw around 400 citizen objects on the screen, memory suddenly disappeared. Tracked down the culprit to a single API call, BUT had to re-write entire mapping/path finding routines to work around it. Simply put, don't repeat the same lookup for data over and over, cache it yourself.

What did you learn?
I had never used the TILEMAP system in Unity, I had never made a game with a map this big before. It has some interesting quirks but can be really powerful. My map maker said it was very similar to RPG maker.
I also never drawn sprites in runtime which I had to do for the mini-map (actually its so big it fills the entire screen). It took a bit of trial and error but its working great.
I spent a day writing a new Text box which meant handling alignment and justifications, more sprite drawing by hand.
Other new things I haven't done before was the story text/cut-scene controller. It helps to make a cut-scene engine and use data-driven program so changes are easy and won't break the game.
I wish I had more time to spend on the AI for the citizens. They are pretty good but I wanted to put in time of day decisions, emotional decisions, etc.
All these bits of code and experience will make the next game come together even faster. This was such a good experience.