No, it's not too mean in midrange since it's literally just a 3/3 that very occasionally comes back to play from the bin.
No, it's not worth it specifically for aggro madness either. You might sometimes be able to bring it back occasionally, but I think most of the time it just ends up as a 3/3 for 3 with a "block deterrent" ability in aggressive decks. The fact is, aggro madness is a very narrow archetype, especially since green doesn't have a whole lot of madness cards or discard synergies. That's not to say that the deck is bad or anything, it obviously isn't. I think you need to stop thinking about things in terms of "is this card good in one specific archetype" and look more through the lens of "does this card fit into a type of deck."
Think about this deck that you posted today on Cube Cobra. Would you play raptor in this? I'd argue that you probably would not. Why? Because this version of the R/G deck, despite having good top-end madness synergies, is really just a Red-based aggro deck. Since green is your second color that you're mainly using to
bring the beef, you don't really want to be playing a hard-to-cast beater like the Raptor. Meanwhile,
take a look at this deck I drafted. Would you play raptor in this deck? I would. Even though I don't have the best morph synergies on the planet, and even my discard part of the deck is a little weaker than your example, the raptor would fit my curve nicely as a hard to block creature for my 3 mana slot, regardless of wether or not I'm bringing it out of the bin on a regular basis.
Basically, think less about the cute synergies that cards can have and more about what the card does on it's floor. I'm not playing
Aphemia, the Cacophony because of her ability to exile enchantments from the yard, despite the fact that I'm trying to make an enchantment deck work. I'm playing her because she's a decent 2-mana beater for my black decks that
also just happens to be good with my enchantment decks.
So, is a 3/3 deathtouch with Megamorph for
a card you're in the market for? Or, are you just interested because it comes out of the bin for free once in a blue moon? I think once you answer this question you'll have an easier time making this decision.