As you said, I believe this mechanic offers more strategic depth:
-the bonuses (attack and accuracy) you get for weapons are permanent and stay even if you change weapons
-having to switch weapons creates a perfect risk/reward situation: is it worth getting a new effect or higher attack in exchange for losing some accuracy or maybe an interesting effect?
That said, I find the idea of weapon switching interesting, and I'm sorry you found it frustrating. Thank you for your feedback!