WPG is only a ballpark, like its been said a million times. If you have CF lighting your wpg will be higher seing how the light is more effecient, and this still depends on what type/brand bulb you have to some extent. If you have a good quality reflector, this will increase you light as well. CO2 will usually always benefit the tank, so long as you dont go crazy with it lol. Excess CO2 isnt usually attributed to algea or anything, but excess or not enough ferts are, so I would be more worried about getting the ferts right. FWIW i have around 2.5wpg, keep my pressurized co2 at 30-35ppm and dose EI. My tank has never been completely algea free but its better now than its ever been with increased co2 and EI dry ferts (used to do co2 at 15-20ppm and 1 weekly fert dose).
What are your intentions? Do you want low-tech, low maintanence, or high growth/dialy fert dosign?
