After this was added to my part template, I thought I was ready to go. Well something else was controlling the initial view extents because my first sketch of 200 mm x 180 mm did not fit the screen. Experimenting a bit, I found the settings for the initial view extents would be respected if I first selected the original sketch plane from the origin folder then right clicked to create a new sketch.
It would also work if I set the Sketch on new part creation located on the Part tab under the Application Options to a set origin plane.
Both of these solutions defeated one of the great features of Inventor which is to select the original sketch plane during the first sketch creation. Upon further study I determined that the original size and the "Auto-Resize" option for each origin plane was the problem.
I opened my Inventor metric part template and created a rectangular sketch on each origin plane 30 mm larger than my initial view extents settings, in other words 280 mm x 230 mm. I then made each origin plane visible and enlarged it to match the sketches. I turned off the "Auto-Resize" option for each origin plane. Last I made each origin plane invisible, erased my three guide sketches and saved the template.
The next time I used the part template, selected the "Start 2D Sketch" command and selected my sketch plane I was pleased to have room to fit my first sketch without having to zoom out to see it. Actually the initial view extents is much larger than you specified due the fact Inventor allows space around the initial origin planes, so you may want to adjust your dimensions during setup.
It really does not matter because Inventor will automatically size the display of the first model when you select the "Home View".
This was my solution to setting the Initial View Extents, if there is an easier way to configure Inventor to do the same thing, please let me know.