I always find it interesting looking at certain cards' win rates. Classic logbait seems like a fairly solid deck, but princess & gob barrel don't have that high of win rates respectively. However, I play enough very random decks that just have goblin barrel or princess, without having other log bait cards, which must skew the data at least a little bit. Using gob barrel alone, more so than princess I'd say, is a great way to lose. It's essentially giving your opponent a +1 trade every time it's thrown haphazardly at the *princess tower. I know we have sites like royaleapi, but I'd love to see the official SC win rate for a deck like classic logbait.
With all that being said, the princess buff is definitely very noticeable. I had almost completely forgotten about the gob barrel buff, although I guess it's helped a little bit at least
Edit: princess, not king
The Log Bait win rate depends on the League: it's a bit strong in the lower tiers (around 52-54%) but after 5000 — perfect 49-50%.