I'd leave it alone. The same humidity levels do not work for all of us. 70% may be perfect for your conditions while to might lead to problem with someone else. We could tell you what works for us, but you will get a wide range of answers because different things work for different ones of us.
Humidities do not have to be spot on. You are dealing with a range, not an exact number. If you are shootng for 65% and get 70%, you are doing fairly well.
I suugest you remain constant in what you are doing and analyze any unhatched eggs to determine what, if any, humidity problems you might have had. If you start bouncing humidity up and down, how do you know what to correct?
Removing water will not lower humidity unless it reduces surface area. Surface area controls humidity, not how deep the water is in the reservoir.
If you open the incubator now and haver an early pip (could be on the bottom where you cannot see it) you take the chance that you could shrink-wrap a chick.