Why did Yaakov call Rachel before Leah (despite the fact that he married Leah first and she bore him the most sons)?
Rashi: Yaakov's attachment to Lavan began with Rachel, and so, from the word go, he considered her his main wife. 1
Why did Yaakov leave without informing Lavan?
Seforno: Because, when he saw how Lavan had accepted the Lashon ha'Ra of his sons, he was afraid that Lavan would steal from him. 1
He later says so explicitly to him (31:31).
Why did Yaakov call his wives to come "to the field, to his flock"?
Tosfos ha'Shalem (1): He called them to the field, lest others hear. 1 He called them to the flock, lest he abandon his work. 2
Ha'amek Davar: It was to Yaakov's flock, but not Lavan's, lest Lavan's shepherds notice. Lavan had other shepherds tending his animals together with Yaakov. 3
Tosfos ha'Shalem (2): "Melech l'Sadeh Ne'evad" (Koheles 5:8) - counsel is taken in the field.
Even though Lavan has been deceitful for 20 years, and Yaakov must flee, he works faithfully as long as he is there! (PF)
See Ha'amek Davar to 31:22.