I can't remember a lot of solo 3D games to be honest and I need to see some good ones to see how achievable it is to do all the modeling, texturing, programing, and music/sound by yourself.
Unless you have unlimited leisure time and no expenses or responsibilities, it's not achievable. Very, very few individuals are skilled enough as an artist, programmer, designer, and composer to pull it off even with unlimited leisure time.
So you don't do all of that yourself. The key to making a game as a solo effort -- or as a small team effort -- is to recognize your limitations and be willing to make some compromises. I understand the desire to make a game that is truly your own by creating everything yourself, but that isn't realistic unless you're looking at making a simple and very tightly focused game.
Leshy mentioned some of the compromises that you may need to make with a solo effort, but if you can break free of the desire/need to build everything yourself, the scope of what you can create opens up considerably.
In an ideal world, you'd have a team working on your game, including artists to create unique art for your game. But you're not making a full-priced AAA game, so don't hold yourself to the same expectations. (Even AAA studios aren't doing all of their own art in-house anymore; on Max Payne 3 our in-house artists did the major characters and the important environment set-pieces, but a lot of the props, background elements, and minor characters were outsourced to companies in Asia.)
I want to create a CRPG like the ones I enjoy playing. I'm not an artist, and I don't have an artist on my team. The compromise that I have chosen is to make use of art assets purchased from the Unity Asset Store and focus my time and effort on developing interesting gameplay.
This is from a very early prototype that I've been working on. You will likely see those buildings and props in other games. Same with the trees and rocks. I can either make a game I don't really want to make by forcing myself to do everything on my own, or I can make something like this:
These shots are from the first terrain that I created using
Gaia. I've since learned a lot more about using the tool and I've been able to do some more interesting things with it. All of the trees, grasses, and buildings were placed via Gaia's spawner rules (these ones are just using the sample models included with Gaia).
I'm not even writing much of my own code yet; the RPG systems are using
ORK Framework. I have nearly two decades of programming experience under my belt, so it's not because I can't handle the coding aspect. I simply haven't needed to yet, and as a result I've been able to focus almost entirely on designing the game, rather than spending months just getting a basic engine working. Eventually, I'll see what I can accomplish with some strategic re-texturing (or just modifying existing textures) and some different shaders.
As I said above, in an ideal world you'd have unique environment art for your game. In the real world, you can get something like
this for $70 USD (regular price; currently on sale for $47):
You just need to make sure that all of your visual assets look good together; the example above (Make Your Fantasy Game) has some great artwork but it has a bit of a painted look to it, so it wouldn't mesh well with photorealistic assets.
).
