My mom had 5 kids and she told me that she had wanted twins, but didn't think she could have handled it. It was a very nice compliment because I am sure she would have done great (the middle 3 were all less than 18 months apart).
I think personallity has tons to do with how hard or easy it is to parent kids. My first was SOOOOOOOO hard, especially as a infant/toddler. The twins were pretty laid back and actually slept until they were about 9 months old (then they stopped, sigh). If I had twins that were both like my oldest, I wouldn't be here posting, I would be in a padded room! In fact I prayed every day, that they not be high needs like my oldest!
Now that they are 2 1/2, they FIGHT constantly. They both have bruises and scratches and scars from the other one. They keep each other awake or pick on each other to the point of tears and tantrums. If I try to take them out, they just run in opposite directions and fast as they can. I would take twin newborns over 2 year olds ANY DAY!!
I know several other people with twins who haven't had those challenges. Their kids don't abuse each other and they don't run away, etc. I know others with singletons and they have the same problems that i have.
Personality has LOTS to do with it.
Like the op, I love to share my kids with others. My favorite day when the twins were tiny was when we went to a community concert in the park and I just couldn't deal with both of them while keeping my oldest out of trouble. A nearby woman was almost having fits trying not to get up and grab a baby
. I say her and went over and asked if she would like to rent a baby for a while. She was over the moon, and i was able to deal with my oldest in a calm gentle manner!