Originally Posted by FastJake

I always build up my own cassettes to get the jumps where I want them. They may not shift as perfectly as a matched Hyperglide cassette, but I never shift while standing and haven't run into a problem so far.

My most custom cassette (8-speed) is made from four different cassettes and works great: 13 15 17 18 19 21 24 30

I always found myself switching between the 17 and 19, so I added the 18 in between. I never used the 11 so I cut it. The gap between the 24 and 30 is big but this idea came from my Megarange freewheel. I have a close ratio cassette in the middle and a bailout gear when I need it.

To the OP, I would not suggest replacing your 15 with a 16. Maybe add the 16 (if you can find one) and lose a sprocket elsewhere. Choosing ratios on a cassette is always a give and take. Until we adopt Nanodrive we'll never be able to have every gear we want with a perfect gap in between each one.