(Make no mistake, there is romantic elements in his comedies as well. However, as I’m about to discuss, they are seen from the sidelines as opposed to the main stage)
Conflict in every form of Wodehouse (school stories, romances or comedies) seems to be centered around some form of trickery. In The Girl on the Boat, the protagonist Samuel Marlowe spends a lot of the book as a frankly manipulative scoundrel and yet we’re supposed to be behind him. Billie, the girl he’s in love with, has such ridiculous expectations that it’s hard to sympathize with her either. In some ways, they deserve each other but it’s hard to like them.
(Oddly, Jane and Eustace, the barely appearing beta couple, are more likeable because they are honest about themselves and each other. She’s controlling and over-the-top and he’s a shrinking violet but they don’t lie about it.)
On the other hand, Bertie Wooster in the Jeeves stories is endlessly using trickery and connivery and bad judgement in the name of love but he’s doing it for other people. In other words, while Bertie is constantly making a mess of things, he’s not doing it for his own selfish reasons but to help out his friends. He’s an idiot and nitwit but he has good intentions.
And that makes all the difference. Bertie Wooster is a hopelessly incompetent hero but he is a hero. He may not be the hero we want or hopefully deserve but he’s the one we’re stuck with :P
The problem with The Girl on the Boat is there are no heroes.