For one who works in a team, the quality of the boss is very important.
..."boss" is not incorrect, but "leader" sounds more appropriate for this sentence.
Also, the topic is more focussed on supervisory job, and therefore it is better to have referance to the topic and use the word "supervisor" in your proceeding lines.
First of all, a good bosssupervisor should be farsighted.
... This is again correct (farsight) , but "visionary" is a very good key word for this idea.
First of all, a good boss should be farsighted. Only a farsighted boss can set reasonable goals because s/he can see the far future of the team. Only a farsighted boss can lead the team to the right direction because s/he can see what will be going on following important decisions. Only a farsighted boss can be a good planer because s/he knows what's to do step by step. So, if you want to be employed by a team that has a glorious future, chose a farsighted boss.
In this whole para, you use the word "farsighted" in almost every sentence at least once. That gives a repetitive tone to this para. Better avoid that. Also you better back your argument with a specific example, such as highlight some experience with a good supervisor :)