I think it would make a huge difference as you won't have a screen top to deal with. That's the main problem, getting a screen top to be sealed with tinfoil or something else is a struggle. I've got a 55 gallon glass fish tank, have 90% of the top covered in foil, a large water dish half under the lamp and moss in a few Dixie cups and my humidity ranges from 50-60%.

Is that thermometer reading 97 degrees? If so, that's too hot.