1. If you want to have kids, do it
sooner rather than later.
My issue is that kids cost a lot of money, which means you lose quite a lot of flexibility.I want to start my own business within the foreseeable future (probably 1-2 years, currently saving money, gathering contacts and getting more on-the-job experience in the field I want to operate in).
Right now I know that if I save 20k Euros that could easily last me for well over a year, if you have kids - not so much.
EDIT: I'm 27 and have tried doing my own thing that didn't work so well in the past - that 'failure' taught me I should probably get more experience and contacts before trying again. Saving 20-30k Euros (or more) is not the issue and is a sum I can relatively easily gather in a 1-2 years time-frame.