Disadvantages
1. Free time- this is only for a limited time; a 10yo doesn't require that much looking after and for a younger child you can join a baby-sitting circle
2. Spontaneity- I found a new kind of spontaneity in myself when I had children, due to their ability to find adventures in even the smallest everyday thing. Dance around the living room singing at the top of my voice- did I do that as a childless adult? Splashing in puddles or stop to look at leaves- did I do that?
3. Time to myself- see 1
4. Time to do my art- see 1; plus you may find an older child makes a good companion here: Monet used to paint together with his children and grandchildren
5. Time to read- they do sleep, you know
6. Time to listen to a play or a podcast- see 1; plus your child may enjoy listening with you
7. Getting enough sleep- that's usually for a very limited time; older children sleep all night and need more sleep than adults.
8. Coming to work everyday- well, illness excepted, you still can
9. Not having to have a boring routine- after from the fact that small children need to be fed and have their nappy changed regularly, there is a surprising amount of room for spontaneity; it is good for children to learn to cope with a flexible routine. I know people who have gone interrailing with toddlers and been absolutely fine. Toddlers were fine too.
10. Money to spend as I please- you might find you enjoy spending it on your children.
11. Saving money- yes, this is true; though apart from childcare costs, it is often possible to do things on the cheap.
12. Holidays with Paul or friends- holidays with children can be great fun, they see things that you don't.
13. Can stay out as late as I want- make friends who will take it in turn to babysit
14. Not having to find babysitters- see 13
15. Far less stressed- I actually became less stressed when I became a parent, because I stopped getting in a faff about the slightest little thing; I seemed to see a bigger picture.
16. Peace and quiet- fair enough
17. Having a healthy relationship making time and giving love to each other- ime healthy relationships deepen with parenthood, it's the already dodgy ones that founder. Personally, nothing has done so much to deepen my love for dh as seeing the wonderful father he is.
18. Sit in coffee shops updating my blog- my dd works in a coffee shop; she says they make a living off the mothers and toddlers.
19. Having a varied and regular blog- you can still have that: there is no reason why every other aspect of your being has to shrivel because you're a parent.
20. Going to gigs- you can still do that if you have a supportive partner
21. Having time for pets- see 20
22. Time to practice yoga- see 7
23. Going on big walks- small children can travel on your back, older children make great walking companions
24. Going out for dinner regularly- that would depend on your finances
25. Being in the moment without being distracted all the time- see, I'd call being around small children being in the moment: it's precisely what they are (it's the day-dreaming that's a bit harder for the first 5 years or so)
26. Not passing down depression or anxiety- that is a more serious concern
27. Not worrying about your children- now that probably isn't possible; with love, any love, comes worry. Assuming there is anyone in the world you care about, sooner or later you will worry about them
28. Not having backchat or ungratefulness towards you- children have different temperaments and at least some of it you can influence by modelling better ways of dealing with disappointment, But as for ungratefulness, you probably shouldn't start from the premiss that they should be grateful to you for bringing them into the world and fulfilling the obligations that come with that. I insist on mine behaving like decent human beings- I don't think I have the right to insist on them being grateful for something I decided to do for my own sake.
29. No dramas- children, like adults, have different temperaments and as a pp said, it's not always the children who provide the drama (no, mother, not looking at you at all, not one tiny little bit).
30. No fear of mentally damaging your children- this is a very personal thing and nobody can tell you whether this is a valid concern in your case or not.
Disadvantages of not having kids:
- Being amazed at having created your own human being- yes, I'd say that's a definite.
2. Being a family unit- that was certainly something I had in mind.
3. Having someone to care for you in later life- that is a lot to ask of someone who by that time may be bringing up young children of their own, or need to live in a different part of the country to find employment, or have health problems of their own.
4. Watching your child grow- this one I found amazing.
5. To love and be loved unconditionally- as pp have said, this is too much to ask. A child is not a dog; love for a parent needs to be a) taught b) modelled c) deserved. The person who needs to love unconditionally is the parent.
6. Going to sleep knowing that you have lived your day to the full, even if that full is tedious!- that's how I felt. But I also needed my career to feel fulfilled and there is no shame in that.
7. Being present and entertained- or frustrated or bored or laughing like a loon or all of them within minutes of each other.