Please get rid of the silly stuff altogether--or put it in its own book. The silly stuff is IMO not only not very funny, but wastes space, and therefore makes it harder to find the good, crunchy bits amongst all the fluff. That was the problem I had with the original Guide, anyway, and one of the reasons it never saw much use at my table.
I would like to see:
Houri Class or PrC
New skills/feats that give bonuses to interact with those attracted to your gender, bonuses to enchantment spells, etc.
Prostitution tables/costs
Slave tables/costs
How "good was it?" tables
More useful erotic spells, such as Charm Kiss from the 1st Guide
Ritual Orgy magic, Crazed Sex/Free Love Cults, Virgin Sacrifice
Rules on what happens if you become pregnant or impregnate someone while polymorphed outside your own race
"Hot" monsters like the succubus, erinyes, nymph and dryad...
Disadvantages like Lechery, Nymphomania, etc.
Venereal disease info for real world diseases and a few new fantasy ones
Different courtship and marriage customs from a variety of cultures and time periods (preferably rel historical ones)
Different laws regarding "taboo" subjects in various real historical cultures/times
Basically, things that are useful and not covered in the core rules