In regards to the misuse of pronouns, I suggest practicing the use of "they/them" to refer to dancers when you call at dances that use Gents/Ladies or other gendered terms. For example, "Ladies turn by right until you're facing your partner, swing them." Another option is to practice not using pronouns (e.g. "swing your partner"). A traditional dance will likely be much more forgiving (or not notice) any accidental references, and you'll be more practiced for when you are calling gender-free dances. 

I personally prefer to minimize over-the-mic explanations about why and how the dance has been strictly gendered. I think most people are aware that almost everything has been gendered, and that large portions of society have been shifting toward a more fluid and accepting culture. If people are not aware, it would take more than an announcement to provide them with sufficient information, and making a speech tends to focus people on the tensions involved with change instead of just enjoying the dance. If there's a need to make a statement, I just briefly acknowledge that the dance has previously used gendered terms, state what I plan to use, and get the dancing started. I usually check in with people during breaks to see if there are any issues or tension that would call for a brief announcement over the mic. When I'm not calling, I have more time to talk to people in depth, listen to their concerns, and provide more insight.