You can take the bus (for free) down to Indianapolis/Arnage, a good atmosphere down there, some banking has been built up to make it easier to see. Food stalls and a big TV.
Same for Mulsanne corner.
Sadly couldn't make it this year but I did spend almost 22 hours watching it, fell asleep between 3-5am.
It's an amazing event that draws huge crowds. You were very lucky with the weather, almost guaranteed to rain.
Felt it a shame that a LMP2 car didn't win overall, I was hoping the Porsche...