The smartest thing you can do is plan out your game expecting that you can't do certain things.

For example, i can't draw people. I'd make a game containing only vehicles, non-anthropomorphic robots, etc and avoid the problem entirely. This also would have a lot of other benefits, e.g. not having to worry about facial animation, walk/run animations, etc.

Failing that, you can acknowledge that a modern game really isn't something done by one person, and find someone who can do the things you can't. I can't make music either, but i just go and find some on opengameart :)

Good luck!

You have hit on some little "cheats" that can work. The main thing with cheats like this is find a style that you can do, and stick with it. If creating objects out of geometric shapes works, maybe it can be a solid style for you and a game. You can then vary that up possible for a different style, say by using those filters, gradients, etc... In fact, maybe you could learn to create graphics with a vector program(Illustrator, or the free Inkscape).

The way I used to "cheat" for 2d graphics was by creating them as 3d models and pre-rendering them. For whatever reason, 3d was much more intuitive form me, maybe because I'm just creating geometry instead of worrying about lighting/shading. And though this method takes more learning time, and more time for the initial model creation, once you pass that stage, things suddenly get much easier. Need animation? Just do it with that model. Need to change something, do it and re-render any animations you have, no need to redraw a bunch of stuff. Need a bigger/smaller size version, just re-render. The same thing applies if you want to change the lighting direction. There are considerations to take with this. For example, the size can't really be 16x16, with 32x32 being pretty much the bare minimum for most things, and really not that great, more like 64x64 being a pretty good starting size. You also have to consider how you shouldn't model details that wouldn't show up in the final render, but remember to include some things that might show up if you increase size so you already have it in case. It's a balancing act.

I would look into creating Vector art. Vector art is used all over the place on apple ipads and android devices. It is a very familiar style and pretty easy to get a coherent style with it. Just leave out a lot of detail and stay basic. Its also fairly easy to animate figures because each limb is a different part and this type of animation has a very different look then realistic animation. There is a blog on the web that does a fairly good job at teaching vector game art but I dont have a link anymore so you will have to google it.

Abstraction !

That is the best cheat. When you add more layers of abstractions, your art will automatically look more coherent. There are several games demonstrating that a high-level of abstraction looks pretty impressive and good.

So, here are the typically section where you can play around with different layers of abstraction:
1.color choice:
realistic->single color palette->single color palette->monochrome
2. shape:
realistic->simplified->blocky->geometric forms only
3. textures:
realistic->reduced detail(cartoon/TF2)->face colors only/flat shaded->non

Thanks for all responses, i'll try out Inscape to see if vector art is something for me :)

There are several games demonstrating that a high-level of abstraction looks pretty impressive and good.

Just for inspiration, do you have any notable examples?

Out of my head:

Indie shooter with high-level of abstraction: Superhot
High level of detail abstraction and color choice: The Witness
Extreme high abstraction: Geometry Wars
Detail abstraction: TF2
Shape abstraction: Minecraft

There are much more, but I would need to look them up.

1. Abstraction will help you to define limits (good for indie/hobby devs)
2. Limits will help you to define an unique style.
3. A unique style will help you to distinguish your title from others.
4. A distinguishable title will help you to attract people.

The worst think you could do as hobby/indie dev is to target realistic/mainstream art.

I decided that my characters would just not have any arms but instead have disembodied circles for hands that I'd float around near by in whatever way that I'd need to. I currently have a way to define hand gestures fairly easily and when I get back to looking at combat I'll look at making the hands move quickly to thrust or swing whatever weapon the character is holding. I'm pretty happy with the results so far. Probably should've done the same thing with the legs & feet.

Other than that all I do is look at the tools that are available in the paint program (usually just MS Paint) and try to figure out what ways I can combine them to get something that I like. Usually that means drawing a small piece of something and then moving that piece into position over whatever base I have for the sprite. I try to keep it as much of an outline as I can so that I can make the area transparent and play with different textures or gradient fills. And while working I try to think about ways that I might be able to reuse the sprite or pieces of it.

for pixel art / textures:
1) if it's symmetrical, only draw one half. copy and flip when done.
2) draw big (like 4x both dimensions), then shrink it down to hide tiny defects and get automatic antialiasing
3) noise functions can sometimes make things look like they weren't made in only 3 minutes when they were totally made in only 3 minutes.