Yisachar and Zevulun; Another Model, b'Zman haZeh?...
From Hirhurim;
The Yalkut Shimoni (par. 960) writes: Click here for more

שמח זבולון בצאתך מלמד שהיה זבולון סרסור לאחיו והיה לוקח מאחיו ומוכר לכנענים ומן הכנענים ומוכר לאחיו.

Rejoice, Zevulun, in your going out -- This teaches that Zevulun was a broker for his brother and would buy from his brother and sell to the Canaanites (or merchants) and buy from the Canaanites and sell to his brother.

In other words, Yisachar was a local merchant, which allowed him to stay at home rather than travel. Zevulun was a traveling salesman who enabled Yisachar to stay home, which presumably allowed him more time to study.
According to this version of the midrash, both Yisachar and Zevulun were businessmen. Neither learned Torah full-time. One, however, was able to choose a profession that allowed more time for religious study and the other chose a more challenging profession to enable the other to have more time.

This is an important lesson for those at the time of their lives when they are choosing their professions. There are different kinds of jobs and you need to choose one which fulfills your goals in terms of time consumption. You can choose a profession that allows you more time to study Torah or you can be an enabler of Torah.

A recent issue of Jewish Action Reader (v. 70 #1), had a piece featuring several people, mostly in business, who managed to be just such Zevulun’s. R. Gil concludes with the obvious, but something that, regrettably, must be stated;

Of course, you can be something else entirely. There are more tribes than just Yisachar and Zevulun.

Also "of course"; they are other tribes - which is to say, whatever ones derech, it must have something of a communal component very close to the core. But how does one manage such a range of choices, in life and profession? Suggestions from R. Cherlow/Sherlo (here), and R. Yosef Blau (here).