Charlie, Condensation is a problem for everyone, some more than others. I would suggest larger sofet vents like you were talking about. But for your situation I would suggest a Dehumidifier. This is something our AC/Heating Company has suggested and they work great and they are not very expensive. Here is a little info on them.

A dehumidifier is used to remove excess moisture from the air. Some of the most common indications that you may need a dehumidifier are:

Wet stains on walls and ceilings
Stuffy feeling in a room
Rotting wood
Condensation on windows
Musty smells
Allergies (if the air in your home is too moist, it will encourage the growth of bacteria and mold, common allergens)

A dehumidifier removes moisture from the air. The usual technique used to remove the moisture is to condense the moisture onto a cold surface.
Anyone who has poured a cold glass of iced tea on a hot, humid summer day knows that moisture will condense on the glass. When air cools, it loses its ability to hold moisture; in the case of the cold glass, the moisture in the air condenses right onto the glass. If the glass is left on a table long enough and if the air is very humid, a significant puddle of water can form. You may have noticed the same phenomenon in any air conditioner. The moisture in the air inside the room condenses onto the air conditioner's cold coils. If it's a window unit, the water drips out the back of the unit onto the ground.

A dehumidifier is simply an air conditioner that has both its hot and cold coils in the same box. A fan draws the room's air over the cold coil of the air conditioner to condense the moisture (which normally drips into a bucket). The dry air then passes through the hot coil to heat it back up to its original temperature. That's all there is to it!

Here is a good link on dehumidifiers