Our babies will be 18 months apart, it was the same or less in my husband's family of 6 kids, and it seemed to work really good, as they were really close friends, were able to enjoy activities together, because of the clothness in age.
Also I was asking him a lot about his personal feelings when he was a child, since he had to share attention with a few of his other brothers and a sister, and both he and his other siblings said that they did not feel the lack of attention, as they were included in all the activities, and were able to share interests ( even if some things were somewhat of a review for them,
) Differently from some of the friends from the families with much larger intervals, where some of the older siblings felt that all of a sudden the new baby was their responsibility, and they felt that they did not had the attention and time they needed anymore. Of course in all cases, things can be corrected with lots of love, wisdom, communication and prayer.
By the way, all the children (6, with year apart between them and a set of twins!) in my husband's family were homeschooled, achieved quite unprecedented skills in performing and music (did TV performing in Asia for most of their childhood years, alongside with national celebrities), and they are ones of the most healthiest folks I know around (My husband never needed to have dental work till his wisdom tooth,
, his brother is prominent triathlete now, etc ).
So, while I think it is personal decision, and in many ways it is also in God's hands, I just wanted to share our personal family experience and to encourage you that if that is the way you would deside to go, it could be a positive experience to have your children pretty close together, and there are plenty of benefits. And you should not worry of sharing attention, you will have enough for everyone, and children benefit from their time with each others as well