Agreed. The story was told by the end of Season 5. Personally I hated the angels and especially Castiel who was played by an extremely bad actor. He was okay in 4 and 5 but anything after that involving him or the angels was tedious to get through. It was so clearly not working anymore that they wrote him out at one point but ended up bringing him back because of the backlash from (I presume) viewers who thought he was hot. Sam was a bad actor too but the chemistry with Dean helped offset his bad acting even though I think he actually got worse as the show went on. Supernatural was a great show for the first 5 seasons but the other seasons and focus on Castiel tarnished it.