My older two have about the same gap you'll have. DC1 was a bad sleeper for her first year but then got better. DC2 was a good sleeper (by which I don't mean he slept 7-7 or anything, just that he woke for feeds 4 hourly and went back to sleep, which is what I had believed babies did before I had one, then thought was just a myth after I had PFB :o )
I found 2 close in age excellent because I was in small child mode, I was a "good parent" doing all the toddlers groups and craft and baking and puddle jumping and duck feeding and poo sticks playing and painting etc. etc. when they were small.
I had DC3 when the older 2 were 5.5 and 3.5 and it was much, much harder having older children on a totally different schedule, need ing to be not just up but dressed and breakfasted and out the door at a set time, and more significantly with school runs and activities and playdates and fitting that around a baby and small toddler - I often think DC3 spends a lot of time as a parcel, just beeng schlepped around while I take and fetch his older siblings places.
As DC3 gets older and wants hobbies and playdates in his own right it is hard to fit his own activities, sports and playdates around the pre-existing ones of his siblings, plus I am starting to "want my life back" and am working more, meaning he's in childcare more than his siblings ever were, and that will continue with him going to after school clubs which they never had to right at the start of school etc.
Two close in age was way easier than a gap, for me.