After the yoke decreases, in addition to the steeks, there should be 196 stitches in total, or 98 stitches on the front and back of the neck.
Knit the yoke section plain, until it is--in total--3 inches deep. On the front of the sweater, knit 49 stitches (half), cast on 10 steek stitches, and continue knitting round marking the stitches. Knit the next round plan, and then decrease one stitch on either side of the steek, every other round, 21 or 22 times to shape the neck (42 or 44 rounds). Knit plain from here to the end of the sweater. After the first 2-3 inches of decreases, you may choose to space out the decreases more for a gradual slope, though I wouldn't.
Meanwhile, when the yoke is 7.5 inches deep, set aside at least 26 stitches in the middle of the back for back-of-neck-shaping, cast on a 10 stitch steak, and then decrease on alternating sides of the steek over the next inch and a half, until the number of stitches decreased at the front is exactly equal to the number of stitches decreased at the back.
When the yoke is 9 inches deep, in the last round bind off the middle two stitch of both of the armhole steeks, ending with knitting across the back one last time. Turn the work inside out and using a three-needle bind off, join and bind off the shoulders.