Digital Watch w/ Changing Background Colors

Hello kind folks of the Arduino Community,

I'm looking for some guidance on a project I'm just beginning. As a beginner a kick in the right direction or any helpful tips are both very much appreciated. Please excuse any incoming ignorance you may be about to read.

Short & Sweet:
I want to build a round watch that displays the time along with changing background colors based on the time of day. So the background color will change based on time of day.

Long Winded:
I've done some initial research and am getting the feeling that a lot of this is over my head knowledge-wise, which is my reasoning for reaching out for initial help. Obviously, I expect there to be a fair amount of experimentation, failing, and learning based on those failures. So, what I'm reaching out for is some (any) guidance on what direction I should head in (in terms of displays, controllers, batteries, housing, programming, really anything y'all are willing to share).

Based on some initial research I'm thinking that a TFT display may be the best option for displaying some vibrant colors, something akin to this. Something in the ballpark of 1.5 inches and round is ideal.

In terms of a controller, I have no idea. Arduino seems like a good idea especially considering their line of smaller wearables, like here. But I'm unsure if something like this will work for what I want to accomplish.

I'm at a complete loss when it comes to powering this thing, what battery will be powerful enough to last for long periods of time, display vibrant colors, the time, and also be somewhat small (I want to avoid, as much as possible, having this look big and gaudy - sleek and pretty are key). Some level of trade-off will be necessary here, I'm sure.

All of this also I would ant to be capable of fitting into a round housing, for a more traditional watch look. In terms of the housing, I have a friend who does 3D work who wants to help by building up some prototypes that I can have 3D printed based on measurements I send over to him. From there straps and such will be pretty easy to find.

I know there are RTC add-on modules for telling the time. Is this the best way to go about displaying time? They are quite small from what I've seen, but is there an alternative to save space?

So, as a list of questions that I'd love some help with:

  • What display should I look into? What brands do you like? (hopefully something in the ballpark of 1.5 inches and round)
  • What controllers should I be looking into? Are Arduino's line of wearables a smart option?
  • What about batteries? What is small, powerful, and long-lasting?
  • Is 3D printing my own custom housing a good idea? Is there a better alternative?
  • Is a RTC module the best route for telling time?

If you've made it this far into this novel I truly appreciate your commitment to potentially help, and I hope to hear your suggestions and thoughts. Thanks!