Don't worry about vocal characteristics (like accent and pitch); they'll be too hard to maintain over the long run, and will just annoy the other players.

Instead, show how your species is different in culture and mindset. Choose a normal human concept and break it, showing what your species does instead.

For example, let's say your species doesn't consider children to be sentient, full members of the species. But, your species considers adults' lives to be sacred, not to be lost for any reason. This will impact your responses to situations, thereby marking you as something different.

• The party finds a child crying that their parents were killed by some kind of beast. You act surprised that the party is paying any heed to the babblings of a child. You assumed they would leave it alone wherever they found it, expecting it would probably die in the wilderness. After all, hatchlings without a nest have no chance to become adults.

• The party finds out that some violent criminal they delivered to the king is due to be executed. You assume the party is now going to mount a rescue mission, no matter the cost to themselves.

What if your species considers anywhere they sleep to be their own territory while they're there?

• The party is invited to spend the night at the home of the local earl. Understanding that this is the earl's way of inviting you to share in the ownership of the estate, you start asking about the financials of the place, wanting to know how much the servants are being paid, how much is being spent on the grounds, etc.

• After the incident with the earl, you make sure to sleep outside whenever visiting a town, so as not to lay claim to anyone's home.

What if your species has no respect for dead bodies?

• The party is horrified to see you butchering the corpses of the bandits they just killed. You, of course, are just trying to look out for the group by providing sustenance for everyone. No reason to let good meat go to waste out in the wilderness.

What if your species has no hesitation to give up their life when it would help the greater good (like with bees)?

• The party is pinned down by a sniper that they haven't been able to find yet. You intend to walk right out into the open so the sniper can take their shot, expecting to die in the process, yet revealing their position to the party.

• The party captures an enemy officer and begins questioning him about his army's movements. You're bewildered that he allowed himself to be captured instead of committing suicide so that his knowledge couldn't fall into the wrong hands.

Yes, you can

You are wielding a weapon that threatens adjacent squares, and using both hands on your polearm does not interfere with the use of the armor spikes. Thus, you can make attacks with them and threaten the squares they reach.

Note that there is usually a hefty gold cost to doing this, as you have to pay for two weapons instead of one. Typically a reach-weapon-user’s armor spikes lag quite a bit behind his main polearm in terms of special abilities.