An awesome show becoming an ok show and then ending as a terrible show is not worth recommending for anyone.
For me Lost, was a great show, with highs and lows, with fairly good last season, with a very disappointing and confusing last episode. Still worth the ride in my opinion.
If you feel characterization is the most important thing, and the emotional connection to characters or having highly evocative emotional moments in the narrative is what makes it worthwhile then you will probably like Lost quite a bit, but you might hate GoT (given my understanding that the last season fucked up major characters for shock value - I can't speak directly to it as I haven't watched it)
So based on that my wife still talks about how great Lost was, and if it gets brought up the first words out of my mouth will not be complimentary.