I suppose there is no single answer to this. It depends on your situation, your childrens ages and personality and luck.
I have dd(13) and ds(9). I spend most of my time refereeing or defending myself against accusations that I love / go easier on or spend more time with the other child.
An example would be dinner last night ds doesn't eat cheese sauce and dd doesn't eat tomato sauce so we have pesto which I hate but it's easier than kids that wont eat.
It descended into an arguement because dd was looking "wierd" at ds because apparently he was breathing "too loudly"
It's so pretty and exhausting.
Ds is super social and we have a stream of friends in and out all day. Ds is in his element in the loud and crazy but it drives dd mad as she is quite introverted and has a lot of homework to do so needs a lot of peace and quiet.
With the exception of the avengers they don't like the same movies so no cinema trips or family movie night.
Museums etc.. are the same, dd could spend all day at an art gallery ds is round and out in seconds. Ds loves interactive stuff with workshops but this would be hell for shy dd.
The only time they play together is when they are in trouble and are trying to impress dh and I 
In my case 2 is not easier than 1.
Tbh life seems to be mostly a compromise for both of them and I spend a lot of time feeling guilty that they miss out on stuff because it's not suitable for both or worrying that I am not spending enough time with each.
However that said, they have their moments and can be sweet together, they do support each other through bad times and they often surprise me with their generosity to one another so while it's not easy for us 2 is perfect 