Highly recommend a viewing platform/grandstand - gets you a much better view and not crowding up to a fence line. It was pretty quiet in the morning when we got there last year (Sunday)
No problems getting a good spot throughout the morning sessions.
The e-Village is worth a visit and if it is still as accessible, find the pit-in-road, can walk almost right up to it and no high fences at the end. Can get amazingly close:
Since there is a big gap before the race, most people on the stands drift away - get a good spot and hold it as the grandstands will fill up (three people deep) during the race. The views are pretty restrictive thanks to the trees but the experience is good fun, hopefully you will get a grandstand with a big screen, most of them seemed to.
Go to the e-village at the end for the podium, again can get really close and a great finish to the day.