I don't believe in rushing to have kids. My first two are 5 years apart, my next two are 3 years (4 school grades) apart, and I just found out I'm expecting again and my youngest is 5. I like to really enjoy their early years one-on-one. I don't think it has impacted their relationships with each other for better or worse. They still love each other and they still fight.
But, since you are already 33/34, I can understand your feeling of urgency.
So here's my two cents as a pregnant mother of a 13, 8, and 5 year old:
It's easy to take a baby anywhere. I've had more than my share of +1 dates with DH. It's when they get to be a toddler and want to explore and don't want to be held or in a stroller, or when they're 4-9 and suddenly everything is so boring but they aren't old enough to be home alone - that's when it's hard.
But then there's the added complication that the expenses are exponential. If you want to go somewhere, each person needs a bed to sleep in. Each person needs 3 meals. Each person needs an entry ticket. And as they get older, these expenses get higher. Teens won't share a hotel bed. They eat off the adult menu. They need an adult ticket. For this reason, if you want to maintain your lifestyle, I would stick with one.
But DD13 has always maintained that she does not want children. She has never been maternal. She doesn't even like animals. Would you be ok if you never had grandchildren? Your odds of having grandkids are slimmer the fewer children you have.
I know it's horrible to think about, but you do also have to consider - what if something happened to my one and only child? My dad's wife has a DD who has refused to speak to her for 5 years, and she doesn't know why. She was always a doting and loving mother. Or if there's a medical issue, perhaps you'd rather focus only on your one child.
My cousin is an only child. She has no family left on her mother's side - They've all died except for her mother. Besides our shared grandmother, none of my side of the family lives near her. She will never have siblings or nieces and nephews except by marriage (& there are currently no prospects for marriage). I think it has sometimes left her lonely, but it's also given her time to really grow and develop her own interests and talents.
My DD8 and I had very clashing personalities from the start. She is a firey little redhead who wants to run the show. You have to ask yourself - what if DD and I have nothing in common? Would I feel better knowing I had another child with perhaps more in common with me? Or, alternatively, what if the new child and I have nothing in common?
I do want to reassure you that DD8 and I were able to overcome our initial struggles. She still has almost nothing in common with me - she's sporty and mathematical and is learning to play the cello, but I enjoy celebrating her achievements. I even learned to like softball.
Which is another can of worms. Each child has their own interests, and they take time and money. DD8 plays softball nearly year round. And then she asked to also play volleyball this year. And join after school clubs. It's very, very time consuming. We're at sports practice 3xs/ week.
Then, after 2 girls, I really wanted a son, which I got. I wanted to experience the other side of parenthood. Do you have feelings like that? Would you feel your family is incomplete without another? Would you be ok if the baby wasn't the gender you were hoping for?
DH and I had decided to go for 4 from very early on in our relationship, but with an open mind. As time went on, we never felt our family was complete, but we also weren't rushing into anything. That would be my ultimate recommendation - do what feels right without rushing or waiting for the perfect time. I had someone tell me once that if I wanted a child, I should just go for it because there never was a "right" time. You'll never be exactly where you hope to be. I've found that to be very true.
Sorry, I know this was long, but I do feel there's a lot to consider either way that you may not be thinking about when they're this young. You also need to remember that pregnancy tends to get harder for your second. Your body "knows what to do" so it seems everything is magnified - the nausea, the bloating, everything. Is that something you're prepared for with a baby at home? Or would you rather wait until she's out of diapers or perhaps more independent?
I have zero regrets about dedicating my life to my kids, but each person has their own ambitions. I can guarantee that your life will change more with each child, but that's not necessarily a bad thing. A friend shared a question she was asked that ultimately helped her decide - "In the end, would you regret having more kids, or not having more kids?"