I'm a big Wario fan, so I'll try to give my non-prejudged view on the game.
Currently I'm at world 2, level 2. The fun-factor of this game is really high, I heard it's short, but so be it. The fun is what you make of it. I must say that I don't understand the high delay, the gameprice and the endresult when it comes to both parts. But for me, I just wanted this game badly and enjoy it even still. The replay value is the fun factor, if you don't see that, that value might be low. But did the old Mario games have replay value? Yes? Why, ask yourself. If you think this game is short, well .... to me, so were a few of those.
Of course, they made a few strange gameplay things. Health is never an issue, especially when you play a lot of action, which I like, you always have enough coins. Reviving yourself for a mere 200 coins at a Boss, which means you start with FULL HEALTH and he again his his low health, or the way you left him .... come on .... this just CAN'T be Nintendo's decision, must be development, at least I understood another company developed it.
In any case. I adjusted my playstyle to it now, since it feels like cheating. Even if it's in the game, something HAS to make it challenging. So I just replay the entire field if a Boss kills me, after using it for the first time, it just DIDN'T feel right, normally when I get a boss, I feel like I accomplished something. The bosses are very fun though, they came up with a few nice ones.
Another thing I changed was, when I'm in the mini-platform games, I force myself to get ALL the coins, I won't leave until I do .... there's no penalty when you drop, which is another strange gameplay decision. So I made it a bit harder for myself, it's all about the way you want to play. I like it this way, BUT as a sidenote, I think development should have thought better (Did they at ALL?) about these things.
Again, the fun factor is high, like Wario should be.
Marco