Hi David.

1. What is the best view mode for flying the airplane whereby you have access to the MCP, and to be able to see the PFD, ND well enough for some hand flying (along with auto flight), along with the Upper Center Display and easy access to the CDU.
There isn't really a single position that will give you a view where you see all those things AND to be looking forward through the window. I resized some of the 2D gauges (DSP, EFIS, CDU, MCP and RADIO STACK) so they don't fill up the scereen when open. So what I do is have the SimIcon 2D Panel open, then I select the items I need to view, when I need to view them, then close them again.

2. The Overhead is very dark in the day time. I have turned on the storm lite, and Master Brightness etc all the way up.
Mine is fine during the day. It is only hard to see during the transition from day to night and night to day, so I'm not sure why yours would be hard to see during the day.

3. I can't seem to start the engines. Have tried both auto start and manual. I get rotation, but no light off. I can't figure out what I'm doing wrong.
Press CTRL+SHIFT+F4 (the default Mixture (full rich) keyboard command).
OR.
On your default flight for FSX, make sure that the mixture lever(s) is set to 100%.
Either of those should enable the engine to start.