If I were to give advice, I'd say we're all just people. We might have cultural differences and our formative years might affect a few things, but we all have wants, needs, ideas. RR is right, effort does play a part in it. I don't tend to RP as women, but I do write from a woman's perspective a lot in my original writing and its pretty much the same as writing from a man's perspective because I have their motivations and backstory plotted out. I'd say there are a few harmful tropes I tend to notice you might should watch out for when it comes to men writing women and women writing men. 

Men often write women as sexual objects, but they also tend to make women helpless and complain-y. 'Men writing women' is a good subreddit to google. On the flip side, women tend to make men controlling, dramatic, and incompetent. There's about 8,000 YA novels with a male protag who gets angry with no provocation haha. 

I'd say if you avoid those tropes, you're writing people more realistically than 80% of published authors. And even if we go back to race and culture, at the end of the day as long as you do a bit of research it won't be too difficult to get right if you put in the effort. 

Now trying to write for Eldritch Abominations from the deepest reaches of the universe is a different animal... but that is not for idle chat.