First, are you planning to leave space to turn vehicles and equipment? You may be towing equipment (sprayers, trailers) and that will take even more room to turn.
If you plan to plant vinifera, you don't need 8 feet between vines. Four feet spacing in the row is the recommendation for vinifera. I think you are in zone 6a; check the hardiness and the growing degree days for your varieties. What are the local vineyards growing?
It looks like you have 8 feet between the rows; that may be enough for your tractor but a truck will be a tight squeeze. We have 9 feet between a few rows and a Dodge Dakota barely fits - we nearly lose a mirror on the trellis posts - especially on the slope and wet grass. You will be harvesting in the early morning so you'll need to keep all that in mind.
Finally, I understand the plan to plant in an orderly fashion but rather than skipping rows, consider shorter rows and add on by lengthening the rows in later years. Depending on your soil prep and plan for trellis construction, you may find it too hard to get in between established rows. You will be covering a lot of ground to spray, train, thin, harvest.... We didn't put our trellis in when we planted our first block and discovered it was too hard to get equipment in the established rows.
It does take a lot of planning both on paper and in the field. I walked miles back and forth, measuring, laying off rows, marking vine and post locations. Do your homework on varieties; I can't stress that enough. Look around this site and see how many people complain that a particular variety won't grow or ripen in their location.
Good luck!
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