Seriously, that wouldn't be too big, in my opinion. My one objection to any of the tips I've used so far is that they're just uncomfortably small, even smaller than cigarette filters, and then the majority of them taper inward. I'd be a fan of a big one that didn't reduce in size beyond the tip of the tip!
I need to put dimensions up on our site. The standard tip is bigger than it looks. The Red Dino Bone Ming sitting on a tank that I posted earlier is 3/4" at the base, 1 1/8" Tall, and 7/16 at the tip. This one is bigger than a standard tip. I can make them however you want. Well there are some limitations.