What do you mean by "huge personality"? You can try bringing a second rabbit to your home even if there is never any guarantee about how your rabbit will like it. Some rabbits don't share our love for bunnies, and some rabbits just hate each other - you can't know before you try. It is not that frequent but I've met several rabbits who couldn't stand their housemate and there was nothing you could do about it. If you decide to do it, take a female. Two males together is not unheard of but it's a real gamble and it's not easy if you're not an expert in bonding rabbits (of course, there are rare cases of 2 males getting along together perfectly from the first time the meet, but I wouldn't count on that).
Having a neutered male, you're in the best position to make a successful attempt at bonding, as males generally accept females quite readily on their territory. You can take a baby, but know that you'll have to keep her separated from the male until she's spayed which will be pretty inconvenient. Don't think that because your buck is neutered he won't try to breed with your female - in my experience one of the 2 rabbits having hormones is enough to start the process - and chances are you female won't take it well and it might end up with fur and blood everywhere. Also, hormones are stimulated by the presence of another rabbit in the house so chances are your female will be very hormonal (spraying urine, phantom pregnancies, territorial kind of hormonal) and you won't be able to have her spayed before she's around 8 months old depending on the size of the breed. Take it from someone who lived through it all before : of course, it's possible that none of this will happen but it might and it's something that you better think about. I wanted to throw my new bunny out the window 20 times a day before she was spayed. And I washed an unbelievable amount of piss on all of my furniture.
So, if you have patience and a separate room to keep her in for around 6 months (plus one after the spay) you can proceed with the baby. If not, an already spayed adult female might be a safer bet (plus, you'll be able to give the rabbit back if it doesn't work out with yours which will save you from living in a house where you have to close the doors to avoid a blood bath everytime the rabbits cross path).
