It has some pretty awful design choices. Some of the later level design is absolutely attrocious. The wisps hurt the level design as well and the forced gamepad bullshit really hurt it. Though that aspect was patched out for the most part. Lives system was really poorly implemented too and the game doesn't give you enough lives given the amount of times an average person will die. But again this is something that was patched since now 100 rings does get you a life. The game also locks some parts of the game behind animal requirements, forcing you to play shitty minigames to progress. An awful design choice right there. The controls feel really off at times too, especially in 2D sections.
Lost World definitely isn't what I would call solid. It has highs and lows and overall is worth playing and has a lot of potential, but you have to know you have to put up with a lot of shit. It's a mixed bag.