my brother and i are 22 mos apart, my husband and his 2 brothers are 18 mos apart, and he's the middle and his step brother is 6 mos older than him (so 4 boys with in 3 years of each other). we both loved having siblings close in age. 3 of my cousins all had their kids 4-5 years apart, and are now finding it difficult for family activities/vacations - boy 13, girl 9... they are just into different things.
my kids are 23 mos apart (girl will be 3 in august and boy will be 1 in july).... it's a bit hectic right now, especially now that my son is more mobile and can now "chase" after his sister to get things.
but in the long run i think it will be better that they will be realatively close in age.
from my perspective growing up with a brother, we were close but we were also into different things being different gender.
my husband with all boys, they were each others best friends and always someone around to play catch with... but they also got into alot more trouble together (esp. as teenagers).