Some fair points you've raised, it's not a gender thing for me , when I roll with much smaller guys I'm gonna just play from the bottom and work my guard retention, sweeps etc, I most definitely won't go full competition mode and smash them from the top like there's no tomorrow, I don't see how that would be beneficial for any party, unless the smaller guy is much higher level skill wise, then I'll try my best to rip him another arsehole, usually with mixed effect lol.
If it comes to rolling with women I totally agree , there's nothing worse than the other person lying flat and giving up everything, I find it a bit disrespectful to be honest so I'll play normally with them, I'd just avoid certain things , for example I'll be on my knees when in side control instead of driving my weight through them etc, I won't give them subs , I'll let get into the position but I'll defend from them and se what they do etc that way we both get something out of the training .
I'd seriously consider changing the club if was you, it's ridiculous to get injured so often unless you train 7 days a week etc. Fingers, ribs etc that can happen any time with no fault of the others but if you get your shit cranked after you tap... well , I'd avoid that place, seriously. Also I'd never white knight for some guy(that'd be gay) but I'd stand up to anyone if they came in and started bullying weaker, smaller people .