It still kinda comes back to whether or not you prefer something just because it’s new. To me, new doesn’t automatically mean better, and what each idea actually brings to the table beyond novelty, which would theoretically favor shark man, is still anyone’s guess.
On the most basic level, the idea of introducing a race of shark men does not appeal to me. Even in KI, where we have werewolves fighting robots and ghosts and vampires exist… I think of an underwater society and I start to think of Jar Jar. Even if I expand my range beyond that limited field of view, I still see that as a design choice that’s lacking both in terms of aesthetics as well as potential lore intrigue or even quality.
To make that less vague sounding, the idea of novelty in this particular situation means little to me if the idea itself is less than appealing. I don’t want Undertow, Master of the Lower Depths, rising from the water to battle Gargos on behalf of the sea. I don’t want to hear about how he dethroned Hell’s Hammer and stole his shark queen and how Hell’s Hammer has sided with the invasion with the promise of regaining his kingdom.
I’m also not interested in ARIA doing Cinder / Riptor style genetic testing / modifications on a shark when a dinosaur doesn’t sound all that dissimilar and we’ve had the gen mod on multiple characters.
Now, is it possible that they could make a background that makes me care about shark man, his lore, his people, his plotline, his allies and enemies and motivations? Theoretically yes. But for me, anything a Shadow Orchid could do, any story beats, would have a much lower threshold to become interesting simply based on who the character is , but also where they’re likely to come from or go.
Lore newness favors sharkman, but that alone doesn’t carry the day for me, or so much to make it more compelling. Golden Retriever Men could be new too. That doesn’t make me want them or their backgrounds, histories, character tie ins, etc.
However, if you like the idea of a shark man already, I can very much see this as a point in his favor. Absolutely makes sense. I see people wanting a Street Shark where I already see a Battletoad. I see people wanting a sea creature when thr lovecraftian concept sounds much more appealing to me. If it’s a human with shark powers, it’s stepping on Sadira’s toes. If it’s less human, then I still don’t see why I’d want a sea creature that limits itself to just one particular creature of the sea. If it’s a genetic experiment, don’t we already have that in Cinder and Ripyor.
This is obviously just my opinion though. I’ll keep trying to find in this what you guys seem to love about it. I also don’t mean to bag on your ideas and opinions! Keep it coming and I’ll do the same. 
