Yes dew point is the maximum, when the air is saturated and moisture starts falling out of it. Psychrometrics is the science. Enthalpy is the total heat content of the air. When someone says “but it’s a dry heat” it’s absolutely true. More humid air has more heat content than less humid air of the same dry bulb temperature. Your air conditioner is removing about 80% sensible heat and 20% latent heat (moisture removal).It’s bringing the dry bulb temperature down quickly, the enthalpy is going down, but it’s not removing enough moisture (latent heat). The warmer the air, the more moisture it can hold. Relative humidity (how much moisture the air can hold at a given temperature by percentage) may actually be going up as the temperature is going down. This is why I say your unit doesn’t fit the application. You need one that will remove more latent heat. This is done by moving less air across the coil while at the same time reducing the capacity of the unit. It lowers the dry bulb temperature slower giving more time to remove latent heat. From what I’ve read (cause I have no practical experience having only worked in dry climates), pretty much everyone living in humidity who goes to a variable speed 2 stage unit will never go back.
