Adding an air cooled light hood will always help the heat. Is your transformer (ballast) remote or is it mounted to the hood as some are?

If the air cooled hood or Cool tube has enough air pushing through it and back out the room then it would drop about 8-10 degrees or more. Depending on how large the glass is. A 6" with a 6" blower will cool more then a 4" with a 4" blower would (only makes since).

After that upgrade if that is not enough then add the other exhaust fan. It's best to have a fan that can exchange the air in the room in under 1 minuet.