Does it really matter what type of cross I wear?

It all comes down to a matter of personal taste of what YOU want to wear. However, enough people see it as an ethnic symbol (Irish, Irish decent) to want to "own" it for that identity, kind of like the Greek Cross for the Greek Orthodox (Greek decent) or the Star of David for Jewish folk.

It doesn't matter. It's just a different style of cross. Some people wear crucifixes. I personally wear a basic gold and jeweled cross. The whole point is the display your faith. Really, I'd only say something if an Atheist was wearing one.

The only thing matter if a person confess Jesus as Lord and Savior and live for him and not for themself.

Romans 12:1-2

1 Therefore, I urge you, brothers, in view of God's mercy, to offer your bodies as living sacrifices, holy and pleasing to God— this is your spiritual act of worship.

2 Do not conform any longer to the pattern of this world, but be transformed by the renewing of your mind. Then you will be able to test and approve what God's will is— his good, pleasing and perfect will.

What does the cross mean to you? If nothing then no it doesn't matter. If it represents your faith, then, no it doesn't matter. If ethnicity and your are celebrating Celtic heritage even if you're not Celtic, then no it doesn't matter.

Yes.

If you wear one of those elaborate ones for Greek Orthodox, and you fall just right, you could impale yourself.

It doesn't really make a difference lol, a rosary is a rosary, either one will keep vampires away.

just wear a bullet around your neck, use it once you find your religion

No i don't think it does if you like it wear it and don't worry about what other people think of you