1. Agree
2. Agree
3. Two percent of the atmosphere is comprised of greenhouse gases. Of that 2%, CO2 is less than 4%. Of that 4%, humans contribute less than 4%. By definition, ANYTHING humans contribute is more than would occur naturally, but "way more than would occur naturally" is a little hyperbolic.
4. True, for the most part, but about 1/3 of ALL human CO2 emissions have occurred in the last 20 years. Temperature has been fairly flat over this time period.
5. There are also some positive ramifications.
As for your last statement, those natural variations have dwarfed any human effects (so far).