I'm not a big fan of stories that take popular characters, and change the gender of them. Reboots that change the story just for the sake of change don't really interest me. It worked well for Battlestar Galactica, but none of the characters in the new series were the same characters from the original series (same names/different people/different era). With Star Trek, it's fun to play with the alternate universe scenario, but changing the sex and age of characters doesn't really work for me.
Personally, I prefer Star Trek that continues to develop the series that we knew and loved. Star Trek Phase II is great for this, because it feels like an unproduced season 4. Tying up the loose ends between TOS and TMP is cool. For TNG, I would want to see a season 8, or adventures during the TNG movie timeline.
If I were to do an "alternate" Trek, I would probably do one that took place during the Romulan wars, with a few Vulcan charcaters from TOS in it. Or maybe a series set on the Enterprise B or C.