My wife and I were in the same position as you are when we bought our current home.
While it is very difficult to know what your situation will be in five or six years, what we did, fwiw, is we bought a house that we could afford on one salary instead of two and allowed that margin to largely function as our buffer. This way, if we both continue to work, daycare would likely not be a huge issue, and if for personal reasons we decided one of us wanted to stay home, we could do so without really upsetting our life.
What I have found, now that we are on our second home, is that about ideally a quarter of your monthly take-home pay should be for your mortgage / housing payment, and in no event should your mortgage / housing payment exceed half your take-home pay. And don't forget to figure property taxes and homeowner association fees, if applicable, into the housing affordability mix.
And again, fwiw, we don't live in a dump. We have a very nice house. What I have found is that in most major cities there are nice neighborhoods and "prestige addresses". If you want to leave yourself some flexibility for the unexpected and wonderful events like kids, avoid the prestige addresses unless you are just rolling in dough.