Well, in my opinion, the issue that should be stressed is: internal standardisation within your website. When an interface has been decided on, the buttons shouldn't flitter around the place.

And in reguards to being intuative. I feel intuative things are those things that, through familuarity, are clear in there function, for instance the concept of the 'trash/recycle bin' on a computer. Suggestion: Don't use 3 identical spherical gradients for your interface buttons and hope people will 'figure it out'. (Yes I've seen some terrible flash)

But, as far as utalising the browsers abilities (Foward/back buttons etc..) The sooner Microsoft give Macromedia Internet Exporer, the better. Personally I am sick of the web not being an emersive multimedia enviroment.