Well, you technically blew it when you installed ACR, since you're not meant to have any mods, so I don't see how a male preggers by a townie would be a problem at this point.

And yes, plantsims are perfectly legal - in fact, if you're playing for points you'd score for black sheep on that one. Hell, alien heirs are allowed if the "mother" is the previous heir. Although since you're using mods, you wouldn't be able to keep score anyway - and besides, isn't the legacy challenge just another way to keep the game entertaining for us?

I wouldn't worry about it. Except maybe trying to decide who to use for the next gen heir, since you seem to have quite a few choices now... ;)