Looking back at my last 3 rides, my average cadence was 90, 94 and 90. When I was riding yesterday, even 80 felt slow to me. There is no one ideal cadence for everyone. Even for one person, it's good to have a range of cadence that you are comfortable with at your disposal. There is gearing on your bike and then there is gearing on your body. Most people without any cadence drills will be comfortable at about 60 rpm from my observation. 80-90 is quite achievable with a bit of practice. I'd say try to increase it gradually and eventually you'll find your sweet spot. You can always fall back to low cadence but you can't just spin faster on demand without practice.