Ph.D. application timing I am going to graduate in mid-October from my M.Sc. in Economics and I am starting to think seriously to apply for a Ph.D. However, since I am still completing the writing of my thesis, I have not yet started to get informed in any way about the available programs and I did not fill any requirement in terms of GRE, language certifications and so on. Therefore, my idea would be to do some research work and to send my applications in fall 2018 (thus actually starting Ph.D. in September 2019). 

Do you think this is meaningful? In my mind, trying to write a better thesis and get some other experience in research could be useful for the purpose of the application. But I am also worried that I am kind of losing one year with respect to my cohort of graduates, thus this could be seen as a symptom of uncertainty. 

How an evaluation committee would consider this timing choice?
It depends what you do instead of school.  But I would not worry about falling behind your cohorts.

A lifetime is a very long time, enough time to do and get good a lot of things. 
 My rule of thumb is that it takes about 4 or 5 years to good at something new, meet an important new life goal, get bored, want something new, then start over.  And you get to keep doing these rinse and repeat cycles as many times as you like.  Figure you have a working life of about 45 to 50 years, meaning you get to have at least 9 or 10 important phases in your career.  That's a lot.

If you think of it in that context, I can't really imagine anything much less important than worrying that taking a year off in between your MS and PhD to go do something else might place you behind your cohorts.  After a few years, no one really has meaningful class of cohorts anyway because everyone follows a different path.

Your actual life outcomes will depend more on what you do instead with that year off.  Could you go find an interesting job with your freshly-minted master's or find something else you'd like to do?