Well, I don't like the fact that some countries are very poor and tend to be taken advantage of. I don't know much about that, or what should be done about that. Perhaps when the world is more globalized that will improve. That is going to be a slow process though, and it needs to be a slow process. Globalizing too quickly will do nothing but destroy working and middle classes of the wealthier nations, likely destabilizing the entire world economy.
Now if you mean wealth inequality in individual countries, that depends on the country. Some countries do alright with that and some don't. the United States for example is more comparable to a third world country when it comes to wealth inequality.
As for taxes, we need higher estate taxes on larger estates. Capital gains should only be taxed at a lower rate for people who are NOT in the top income bracket. Corporate tax is fine as it is. However we need to close the loopholes so those taxes actually get paid. Sales tax should be eliminated, it is bad for the economy. What it does is artificially raise prices, which hurts demand. Lower demand means decreased sales, profits, jobs, etc. Income tax should be progressive and should gradually go back to the rates we had in the 60's or before. Real estate tax is fine as is, so is personal property. Payroll tax stops at 250K a year. However I think it should kick back in at 500K. That way only the money you make between 250 and 500K is free of payroll tax.
I have gone over my views on this in greater detail in the past. So that should be pretty easy to find. Basically I am a left libertarian. Some people call it Democratic Socialism. It's not really true socialism though. Certain specific things might be socialized, but the majority of the economic system is based on free market capitalism. I sometimes say that I'm not quite and anarchist, and not quite a socialist, but I'm not too far from those things. The way I look at things is based 100% on logical reasoning and empirical evidence.
What we seem to have in the US right now is rampant propaganda being used to circumvent American democracy. We also have a glorification of ignorance and stupidity. The reigns of the country are frequently given to people so feeble-minded, I wouldn't trust them to care for my cats, let alone manage a country.
I'll leave it at that unless you have any specific questions.