It's hard to calm you all down without spoiling!
The monster isn't the primary focus of the show. About a third is focused on backstory, the other two thirds on happenings on the island.
And as someone who has seen Gilligan's Island
and Lost, I can tell you that they're quite different.
I haven't seen Jurassic Park for ages, but Lost was filmed on Oahu, Hawaii. [Hope I got the spelling right!]
I'm actually surprised that so many people are thinking of dinosaurs, because it didn't cross my mind for a second.
Keep in mind that they're up to episode 14 in the US with no decline in ratings. Whatever you may think of Americans, millions of people aren't going to be watching unless it's really good or really addictive.