Thank you for the comment, I feel special xD
To answer your questions:
1. Yes, the hygiene indicator is coming in 0.08, it will be seen on the bodies of the slaves. And hopefully it will be easily visible and if not then I will probably add it to the womb diagram like you mentioned. Also the showers should now work with slaves cages too, they will take the dirty slave, clean them and return back to the slave cage.
2. I am still working on those bridges and their functionality, so you can expect some changes and I may use some of your suggestions. Especially the idea to connect milking room to growth room. Also you have mentioned that you need the lotion to keep them alive. If you have your slave fully depraved then she should not receive any dmg from sex. I added a short info about it in previous update but maybe it wasn't very noticeable as few other people has mentioned a similar issue.
3. Pretty much what I said at the beginning of point 2 :)
4. Yeah it is kind of dark xD And actually I guess I completely missed that, it is now possible to connect breed room to showers but not to GH. And I have also noticed a bug where shower says you can connect to GH but in GH it doesn't say that.
I hope this covers everything.
Have a great day :)