One more bug in the original: The very first field in Features and Traits has the font set to size 12, instead of auto, so it won't auto-size the font and instead just scroll off into hidden territory.
Anyway, two more revisions along in reconstructing the character sheet. Instead of just duplicating page 2, I put the Features & Traits on one page, and Maneuvers and Knacks on a second page. This gives 78 fields for features (instead of 26 for one page, or 52 with the duplicated pages), 22 lines for maneuvers (enough for a 20th level fighter plus a couple feats that give free maneuvers), and 12 lines for knacks (enough for a 20th level ranger).
There's finally enough space for me to copy over my 14th level barbarian, with enough space to easily handle going up to 20th level. 30 of the lines in the Features & Traits section were stuff that was new to Level Up. With just O5E stuff, it could have fit in the space on the original page (mostly).
There's still some stuff I'd like to change, but I'm less sure about how all it would fit together. It would expand the page count again (from 5 to 6), which feels like it's starting to get excessive, but stuff like followers and strongholds kind of overflows what would have been appropriate on a single page.
I think... I think I can make do with the current pages, and just make a few tweaks. I'll try that.