Alone is not smart...male or female. Not even in a taxi (especially in a taxi?)
I was there last month and I'm headed back in a couple weeks.
CCS airport is one of the worst I've experienced.

Caracas may still hold the world record for murders within a 24-hour period.

If you could somehow get to the rest of Venezuela without going through CCS, you're much better off....I just don't know how to do that short of going into Colombia or Guyana and making an overland trek....which is probably even more risky than CCS.

Caracas left such a bad taste in my mouth. It's the perfect storm of being horribly expensive, unsafe, dirty, crowded and corrupt....and Venezuelan beer is perhaps the worst on the planet.

Canaima is worth the effort.^