Define carefully which goals you want to reach during your postdoc period!
An important rule for a happy life is to define the goals you want to reach and how you want to feel while you are pursuing these goals.
Which private and family conditions do you want?
Do you really want to go abroad?
Long-distance relationship or moving together?
If you go abroad your relationship will suffer Inevitably. In most cases long-distance relationships are not experienced as easy. You can only communicate via email, phone or skype which is of course much less intimate than being together in the same room. In addition, you may feel lonely and get in contact with other attractive persons which may appear as an interesting alternatives for your existing relationship. If children are involved they miss you terribly, you may miss them terribly and you do not participate in their life anymore for quite some time.
Joint postdoc with your partner?
Going abroad for a postdoc together has many advantages. You avoid the inevitable problems of a long-term relationship, you can cope better with loneliness, being homesick and possible discrimination as a foreigner. You share many experiences and challenges which may strengthen your relationship. The organisational and administrative effort is shared which may make it easier. Both partners experience similar working conditions and understand perfectly well the situation of the other. Working together in the same lab allows effective collaboration, participation in joint projects leading to more or better publications. However, it may also lead to unpleasant competitive situations depending on the type of relationship you have. Working in different labs may be better to develop an independent career but comes with the risk that one partner experiences better working conditions, better salary or better output.
Which impact factors and how many papers do you want?
When going abroad you should aim at an excellent publication output. A postdoc period is often short (2-4 years) and does not always get extended. The first postdoc may be followed by a second one but you may also start applying for academic or industry positions. For professorship positions your publication list must be excellent, for industry positions your technical and transferable skills may be more important. To learn more on how to develop a clever publication strategy read more here: What is the best publication strategy in science? There are good arguments to focus on one or only a few papers with high impact factors provided the supervisor is excellent, substantial funding is available and the infrastructure is state-of-the-art. As a rule of thumb I would predict that a very high impact factor publication (IF > 10) means that you will work extremely hard, while 1-3 high to excellent impact factor papers (IF 5-9) will allow you more freedom. You should also consider the working environment – if you go to a top lab which publishes very high, you will probably work in a very competitive environment. Before you apply, you should definitely talk to *several* former and present lab members to get a rough idea about the working conditions. Read more here: The most intelligent strategy to get hired in science.
Which technical skills do you want to learn?
The postdoc time is the perfect moment to learn fancy techniques which distinguish you from others later and qualify you for specific positions only few can fill. We often see PhD students and even postdocs who have mastered and practised only one or two very common techniques such as immunohistochemistry or qPCR. The other extreme are persons who claim to know a multitude of techniques but demonstrate only very superficial knowledge. The golden middle way is of course to select a few techniques which are not completely common and become very experienced with them. For industry positions high expertise in a few fancy techniques may be an advantage. In contrast, for professorship positions your technical expertise often plays a minor role. Some colleagues even have the opinion that a professor should *not* be the best technician in the lab. In contrast, they outsource specific technical expertise (for example via collaborating with experts in the field) or hire a competent postdoc. Thus, for professorship positions technical skills are often overrated by young scientists, other skills may be considered as more important. Read more here: How to become a professor?
Which transferable skills do you want to learn?
The postdoc period is a perfect time to learn management, communication and leadership skills. There is a long list of skills which are considered important for leading a research group in academia and industry. The postdoc period is also the time to develop scientific independence and develop clear ideas about your future lines of research, and on how to raise grant money. Before applying, you should ask former and current lab members whether they have learned these skills and whether they had the possibility to learn grant writing and raise a substantial amount of grant money.
How to choose the best outcomes?
In summary, you should enjoy your postdoc period and make it a good time. You should go for the big wins such as high impact factors, big grants and fancy techniques. However, you should consider carefully the costs for your relationship, family and finances by addressing the questions raised above.