I don't think the poster was trying to be snarky. I think she was legitimately trying to help and was merely pointing out how much difficutly the "mis-spelling" of her name has made her life. It's the fact that having two "ii's" makes it look like a typo, not unique like using a "y" would be, thus the complications that will invaribly arise. And in your case, having the marrige license reissued 3 times does make for a funny story, however having medical records not match up, employment/diploma records not be found, etc. is not so amusing. Especially if it happens all.the.time.
As long as you're aware of all the possible pitfalls that will likely occur (and again I'll reiterate that two "ii's" look like a typo, not a unique spelling), then you're quite within your rights to do so as a parent. I personally really, really hope you give it some more thought. And I'm not trying to be snarky/mean, it's one thing to give a child a unique name....it's another to have a misspelled name that causes one to have to get a passport reissued-multiple times. And those are hard enough to come by!
I was trying to think of a nice way to say the same thing - but you said it better than I could have. I think the name Michael is great for a girl. Different and unexpected, yet familar to most english speaking people.
In Swedish "Michael" is "Mikael". In case you wanted an alternate interesting spelling
The name will still get pronounced incorrectly but hey, who doesn't love a Swede
And in my personal opinion, it has less chance of getting messed up than 2 "i"s.