Simple questions about things

[ZBoyer1000]

Is a strict 11 color palette for each image created good enough for quality pixel art?
Would a quad that bleeds cause any performance issues compared to a quad that does not bleed?
Instead of creating an error message for someone with an old graphics card, is it a good idea to simulate an inferior version of a shader
so that someone can play games without much hassle?
Is it a good idea to index large math calculations in a table to save cpu?
Is it a good idea to automatically change settings in a video game if the frames per second in that video game is below a required amount?

What does this guy remind you of?

[Inny]

Is a strict 11 color palette for each image created good enough for quality pixel art?

Yeah, if you're a good artist you can work within limitations. Only having 11 colors isn't going to make you a better artist automatically though.

Would a quad that bleeds cause any performance issues compared to a quad that does not bleed?

There's no reason it should, but I've never actually tested that.

Instead of creating an error message for someone with an old graphics card, is it a good idea to simulate an inferior version of a shader so that someone can play games without much hassle?

The only thing I'd think would be a problem is that a software simulation of a shader would consume CPU cycles, and older machines without a modern video card would probably not have a modern CPU.

Is it a good idea to index large math calculations in a table to save cpu?

It depends. You won't really know until it becomes an issue and you identify in performance testing that its the calculation you think it is. That said however, if you write your math functions to only operate over inputs and act in a "pure" way, meaning that the only value that comes out of your math function is through the return keyword and none of the input parameters are changed, nor the global environment, then if that function becomes a problem in the future it should be very easy to replace it.

Is it a good idea to automatically change settings in a video game if the frames per second in that video game is below a required amount?

Another "it depends" here. This question is better stated "Should I drop frames or should I slow down?" Different games handle it in different ways and you'll have to test for what works for you. But if you want to be friendly, you could make your config menu where you ask for Video Quality, in addition to a low, medium, and high, you can also offer an "auto", so that the player gives direct consent for you to jump from high to medium in response to framerate dropping.

What does this guy remind you of?

TF2 Engineer

[Luke100000]

Is there a way to 'disable' quad bleeding? Or to prevent this effect?

[cval]

Is there a way to 'disable' quad bleeding? Or to prevent this effect?

Depending on what are you trying to draw with them, you can either set texture filter to "linear" (simplest way, eliminates bleeding completely), or play with BlendAlphaMode while you draw them (if turning linear filtering is not a n option, though effect is kinda weak). There is also case when bleeding looks like a part of another object on texture atlas which quad should not include, then you also play with viewport parameters.
More on BlendAlphaMode page