Hi OP,
Firstly, it is completely your decision. Please don't let anyone pressure you one way or the other.
I am at the other end of the spectrum. I have 3 DCs over 8 years and had my third at 38.
I think that having them close together is short term pain, long term gain. By spreading ours out things were never quite as chaotic as if we had them close together but I am 40 now and have been changing nappies for a decade. I am utterly exhausted and feel pressure in terms of getting back to work and building up a pension etc.
From my experience, going from 2 to 3 was the hardest transition. But that is also because their needs are so different. I have to do school work with the eldest and playdough with the youngest. DS1 wants to stay up until 8pm but I go to bed at 8:30 because DC3 is up at 5:30am. My candle is not so much being burned at both ends as attacked with a flamethrower!
When they are close together, it will be hard for the short term because they all need physical help with personal care but as they get older, they will be able to play together, you can do activities with all 3 at once more easily and you can move out of child phases more quickly.
Either way, you will be ok whichever choice you make xx