I haven't read the manga, but I see what you mean. You can hardly turn your head in this series without seeing grand narrative potential, but more often than I care to say, Fairy Tail plays a little too safe for its own good. However, I retain high hopes of this soon changing.
And yea- The writer clearly aims on keeping things light and fun most of the time, and I respect that, but he could do a lot more dramatic if he desired. Maybe after FT he'll do something along those lines...
I'd rather him not wait. I've grown too fond of this. Besides, no artist who cares about their work should let its latent potential go unused, and if he started another series for the sake of making a more dramatic story, wouldn't it essentially be based on the afterthought of "I wish I had done this with Fairy Tail?" I mean... that would be pretty f**king pointless since he could simply do that with his current work. I know he's all about this being a "happier, more lighthearted" story, but he more than clearly likes exploring other emotions besides joy; it's part of why I picked it up and stuck with it for so long. I think it would be a simple matter of deepening the emotional narrative and integrating a stronger sense of relevant consequence to pick the series up to a more appropriate, deserved level.
There's a crossover between Fairy Tail and Parasyte.
Parasyte is a manga about alien organisms who replace pieces of human bodies, normally the head and brain (at which point they then impersonate people and eat other people), but in the main character's case had a hand replaced and became friends with it's host.
This probably isn't the most accurate analogy (in fact, I'm almost certain it isn't), but I often think of Fairy Tail as "the Teen Titans of anime". I see it this way because (A) their roles in life are seemingly ongoing in the sense that there's always a new threat to confront or challenge to overcome, and (B) the series has a knack for being able to distribute narrative focus between characters in appropriate sums so as to make/keep things interesting.
So the Empire's main attack has begun and Mavis gets to flex her strategic skills along with a call back to the Phantom Guild. Though its a shame that what seems to be the first match that the guy's opponent ended up being Erza. Well if its going to be a stomp, Hiro should at least keep it short so the other guild members get stuff to do.