I own one telescope (an 4 inch fl7 apo) and 6 eyepieces, which I confess is probably 2 too many. Mine are a mixture of ES 68 and 82 of numbers. They are 4.7, 6.7, 11, 16, 20 and 28 mm. The 28 mm 68 is a really very good eyepiece. The 6.7 is my most used planetary eyepiece and if I get the chance my 4.7. However I conceed that I have too many. The 4.7 gets a lot more use than I had imagined, but the 20 mms doesn't get used much and the 11 mm really only for white light solar, and even then the 16 mm could probably be just as useful. I had thought about changing the 16 mm for a 82 degree 14 mm, but the 16 is very good and I have a morbid fear of buying astro gear. Getting it wrong is expensive and I have been very lucky so far judging from some of the stories I have read on here over the years.
On a different matter I have never understood why ES eyepiece are not more popular in the UK, excellent build quality, identical optical quality to TV and less than half the price, I don't get it.