We enjoyed Fringe a great deal. The main thing is not to depend too much on the long-running arcs to make much sense; they go quite a ways off the rails and most get laboriously pulled in in the last two seasons. Watch it a little more show-by-show and enjoy the connected bits but don’t put too much weight on them.
Besides watching for an Observer in every episode (many are just brief cameos), apparently every episode from season 2 on has a clue to the next episode’s plot. F’rex, one has a sign with a fountain pen and rose, and the next ep’s bad guy is named Penrose. None are anything you can figure out in advance, but looking for them in review is fun.
And Walter manages to be a delight for all five seasons. I simply can’t think of another mainstream character acknowledged to be a prolific druggie - he’s on acid about every third episode - without it being turned into a ponderous Drugs R Bad, M’Kay? theme. Walter will say things out of the blue that will make you flinch, blush or say “What the fuck?” right out loud. (“Oh… I have an erection.” [turns to blonde co-star] “It’s not you. I just had an idea.”)
And the fourth episode from the end, seasons 2-5, is the bizarre one.