I agree about the fortuitous casting.
Lost had a whole lot of highly talented, charismatic actors who were cast in the right roles for them. So many shows fall on their faces with the casting. Sometimes the actors can be good but just miscast - Joseph Fiennes in
FlashFoward being one example.
Otherwise, I think it boils down to imagination + discipline - two very different modes of thinking that doesn't seem to be combined often enough into one writing/producing staff. Either you get plenty of imagination and no discipline, resulting in a godawful mess like
Heroes, or you get plenty of discipline and not nearly enough imagination and daring, resulting in inert, formulaic shows like
V and
The Gates.
I also loved its musical selections--whether the orchestral stuff or the pop music like Mama Cass, Three Dog Nights, Sarah MacLachlan, Oasis etc.
I loved the way
Lost had its own unique style. It wasn't afraid to be very strange. The old computers from the 70s, the bizarre orientation videos, all the hilarious, offbeat little touches, right down to the books the characters read. It was a fully fledged universe of its own. Compare those to the very humdrum style that most network shows adopt. Only on cable do you see the likes of
Dexter, Breaking Bad and
Mad Men, which create a distinct style.
Two favorite completely off-kilter moments: the fake Dharma Initiative ad placed in the commercial break and the USS Enterprise zooming thru the LOST logo.
That's another thing other shows could learn from LOST--you can't anymore start out slow and plodding and be given time to find your footing.
...
That was what hurt to some degree in my opinion shows like V, Flash Forward and Caprica.
Too many times, I find that first impressions are the right impression. Of all the shows I've tried that seemed like misfires, they pretty much stayed misfires, till I gave up or the show got cancelled.
Caprica seems to be coming around to what I wanted it to be from the beginning, but overall, it's just not worth it to hang on for a show that doesn't seem worthwhile right away.
As for
V, I'll keep watching because I'm desperate for any semi-decent sci fi on TV and it won't get a third season anyway so I might as well watch it while I can.
To expand a bit on my earlier remark about the fortuitous casting, I don't know if that's something that any show can do
It seems to be a function of budget. ABC probably gave
Lost enough money that they could lure top talent to Hawaii (oh the humanity!

But LA is where the action is, and going elsewhere is an inconvenience if not a career risk), not to mention the budget to shoot in Hawaii in the first place.
For the counter-example, look at
Persons Unknown - the writing isn't bad, but many of the actors are mediocre to awful. That show is obviously being shot on the cheap, which is probably why they're filming in Mexico. How good a cast can you expect to get, under those conditions? With
Lost-caliber actors, that show would be immensely improved.