I just love how tropes which appear outlandish in other fandoms/ships just mesh so well in with this pairing

Like Mpreg? Sure, why not? You don't even need them to bump the uglies for male pregnancy. It's not as if Harry is not literally carrying a bit of Vee in him.

The shard can always absorb some of Harry's life force and boom—you have a successful male pregnancy, your honour. One that is even kind of believable.

Harem, you say?

Well, why should Tom have all the fun? What about the Ring, the Cup, the Locket, the Diadem? Don't they deserve some love too from the Boy Who Has A Lot Of Love To Spare?

I swear, many readers like me, who don't even read poly or/and harem, have been converted to fics that have Harry playing house with his four Horcrux husbands, 5 if Diary survives. Why the hell not?

The Horcruxes really make a lot of otherwise unbelievable tropes come true.