Followup from here.
My adjustments for try #2 of this worked very nicely. I had a sweater like this years ago that I somehow lost, and wanted a replacement. I couldn't find what I wanted on Ravelry, so I ended up adapting this one.
My adjustments were:(a) Only did 3 rows of ribbing rather than 20 because I misread it…and then just went with it.
(b) Due to my big honkers, I added on about another 6 stitches for those, making the sides about 40 stitches.
(c) I cast on 70 stitches for the front pieces too. After doing the 3 rows of ribbing, I bound off 30 stitches to make ties.
(d) Had to add 2 more inches of sweater at the top after the decreases in order to make the armpits big enough. Did the same thing to the tops of the sleeves (adding another 2 inches), which bizarrely enough, worked out nicely.