Apologies for not replying sooner, but one thing about Emma is that she actually doesn't mind if you've had sex with women before her. Hell, the way one of the events is written she's surprisingly pragmatic about it. Her concern is more about what (or rather who) you're doing as you're getting to know her.
Coincidentally, I was also mid-Emma run to try and pin down specific things to do (or rather, not do) in order to be judged a good boy by her and not have to constantly check the wiki/do mental calculations. While I did have to resort to calling upon the slumbering Chea'thulhu to tweak one thing as I was in a hurry, but I can say my plan ended in success.
(In my defense, apparently you can't have a picnic in the park during the first week of winter because of some, inexplicable reason programmed into the game. My argument to that is because of a) the general attire of park goers on that day and b) my eyes were not poked out by any extremely erect nipples means that it was not cold enough to prevent a relaxing picnic. So I'm sticking to my guns on the fact I shouldn't have had to skip forward a month to do that event.)
Now while people would probably a nice guide to Emma, I do think that the way to avoid the major deal breakers would be as follows:
- Don't sleep with Bree.
- Slow down on Sam after she gets married.
- No official girlfriends/slaves.
- DON'T UNLOCK CASSIDY.
While I am able to go a little more in depth into each of those, unfortunately the first draft is a bit nuts, even by my standards. Maybe after a nap and a proofread I can get something out of it.