Looks like as good a place to start as any. I don't see anything terribly wrong with the design. I personally might make the choil area (curve under the front edge of the handle) more of a constant radius or semi circular line. But that's me. I think I'd make the whole design wider top to bottom as well. According to your sketch the handle will only be a half inch deep. And your handle will only be 2.5" long. I'd think you'd want in the neighborhood of an inch at least to fill the hand a bit and at least 4" long. Make a mock up out of cardboard, Masonite hardboard, plexiglass or something similar that is easy to shape. Try different sizes to see what fits your hand the best. I would say, make another drawing traced over this one. Make the lines basically the same except that the top and bottom lines of the handle are 1" apart and lengthen the handle a bit. Then adjust the curve of the blade to work with the wider dimensions. Make a mock up of that and see how that feels.
You have done the right things so far. You collected your tools and some great steel. You have a game plan and have posted a drawing first. Excellent! You can do this. But this is just a caution and some free advice. At the very least it's worth what you paid for it. Some new guys rush in and don't listen to advice. You are off to a good start. Don't rush. It isn't a race. Don't skip steps. There are aspects of making knives that are very time consuming, tedious and take a lot of energy. DO THE VERY BEST YOU CAN AT EVERY STAGE. Refer back to photos of well made knives for reference. Pay attention to details. Use the search function to find as many answers as you can. Almost every conceivable topic about making knives has been discussed a hundred times and can be found with a little searching. If you can't find it or various answers are contradictory and confusing, ask the question here. A lot of very knowledgeable folks will help you find your way. Keep us posted and good luck.