It's really hard to say.
The thing is, I just don't see how you can do an OT styled movie using these turtles. You're trying to make your movie based on the most light-hearted iteration of them using possibly the most intimidating and repulsive looking ones. And if the tone, style, and everything else was the same, it'd still be compared to Bay's other films, most notably Transformers.
I say it's best not to dwell on it. What's done is done.