Today is another good day, as all the things on my schedule goesare going the right way. Today is another good day, as all the things on my schedule are going the right way.

Of course, the instant gratification monkey still annoyed me so much, even though I had prepared some powerful tools to dispel ithim. Of course, the instant gratification monkey still annoyed me so much, even though I had prepared some powerful tools to dispel him.

I changed "it" to "him" because you use male pronouns in your last sentence. I think either way can work in this context, but it should be consistent.

I guess, like asomeone with schizophrenia person, I have to live in harmony with him instead of behavtreating to him aslike a rival. I guess, like someone with schizophrenia, I have to live in harmony with him instead of treating him like a rival.

Or: "I guess, like someone with schizophrenia, I have to live in harmony with him instead of thinking of him as a rival." "someone with schizophrenia" can also be "schizophrenic" : "I guess, like a schizophrenic, I have to live in harmony with him instead of treating him like a rival."