I think the problem is this gym you train at. I don't see what the deal is. You should spar or roll with a girl just like a guy, taking into account size and experience. It's not rocket science. Just like you spar anyone, you feel the person out, find the pace, and that's it. I personally have not run into all these crazy problems you seem to have looming around you.
If anything I think it is a huge disservice to a woman who is training to fight to baby her. I've seen some women do poorly in fights because clearly they did not get the sparring they needed. It's not even a woman vs. man thing.. it's a fighter thing. You don't put your fighter in a fight with hardly any sparring. You don't wait until fight day to see how they react under pressure or how well they can take a hit. It's not a gender thing.
As far as rolling, you do a disservice to the woman when you loosely attempt a submission and move on. Being able to tolerate the positions, tolerate the submission, and more importantly, have the opportunity to escape is all very important to learn. How can you learn that with someone babying you? Sometimes the guy doesn't even have the sub locked in correctly, so it is not worthy of tapping and yet he will move along as to not cause the girl to tap. Don't do this. What's the point?
You try not to hurt your training partners, whether they are men or women, you need them to make yourself better. It's not a gender thing.
I understand some women are different and I just assume if they don't like fighting, they will get bored or decide it's not for them and move on. I understand that a lot of men are noble and good and they understand that it is easier to hurt a woman than a man of the same size, so they go easy... that's fine, your gentlemenliness (if that's a word) is awesome and much appreciated, but the woman will show or tell you that you don't need to baby her.
I have a lot of guys who know me quite well so there's no issues with them, but any new guy I roll with who is trying to baby me I will either tell him, "don't worry, I will tap when you get it" I might have to tell them a couple times, I don't mind doing it and they catch on pretty quick. With sparring, there usually are no words, stand up is just like with anyone, you catch on pretty quick to what level your partner is on and how hard you can go. As I rule, I always set the pace pretty hard with new guys so I didn't have to waste time with them getting comfortable hitting me. They hit me, I hit them, it's not a gender thing.