Gaston is more of a gag series about the pranks and blunders of an office boy. Each gag only covers a page, a bit like a Sunday page comic in a newspaper. Thus "Gaston" is not really a series about travel and adventure like "Tintin" or "Asterix" and Gaston is more of a lazy, accident-prone, childish, bungling idiot than the heroic, daring and adventurous characters of the other series.
In Sweden, we once had this comic book series called "Agent Annorlunda" ("Agent Different"). Interestingly enough, Agent Annorlunda was a blend between a virtually perfect adventure hero, like say Tintin or Spirou, and a more flawed comical anti-hero, like say Gaston Lagaffe. When it came to basic plot-lines, this series was notably similar to "Spirou". Agent Annorlunda got into adventures from all over the world, which were mostly much more outlandish than your typical "Tintin" adventure. And you can tell that the illustrator Johan Unenge was influenced by Franquin, and not by Hergé and his claire ligne style.
But when it came to the protagonist's personality, Agent Annorlunda was goofier and more bung- ling like Gaston. And also, while heroes like Tintin and Spirou never showed any interest in a girl, Agent Annorlunda has a budding relationship with Daniella Doppfinger, the daughter of the local inventor and scientist, just like Gaston is dating Mademoiselle Jeanne. This was of course a very intentional choice by creators Måns Gahrton and Johan Unenge, whose opinion was that Tintin and Spirou were boring compared to their companions.
Unfortunately, it seems like the series never took off as it should have. So it was cancelled in 1992 after only eight stories, when it became more profitable for the creators to focus on other works. For example, they are much more known for the more realistic "Eva & Adam", a slice of life series about a group of pre-teens and their experiences with dating, friends, school, parents and siblings. But I guess that my point here is that you can blend Spirou and Gaston Lagaffe and make it work. Except for that such stories maybe isn't what many critics and readers want, sadly enough...