This is rather a vague question. I can look at Doctor Faustus as a play from a personal perspective, asking, "Do I like it?" To this, I would answer, yes, I do. Marlowe does a pleasing job of telling this famous tale based on the life of an actual individual, though scholars debate about which of several candidates it might be. I would also say I don't like it as well as Goethe's Faust, Parts I and II.
I can also look at Doctor Faustus in relation to other plays, in which case I'd say that some of Shakespeare's plays, like Romeo and Juliet and Much Ado About Nothing, and Goethe's Faust are structured and told with greater skill and interest. This is particularly true of Faust Part I.
I can also look at Doctor Faustus in an analytical light and criticize its structure and other internal devices. I would say that structurally, it has some interest because of the Chorus, the antagonism between Faustus and Mephistophilis, and the heightened emotion of Faustus's last struggles. I'd say the presence of a Greek style Chorus allows Marlowe to make moralistic points from outside the plot line so that the story itself isn't sacrificed to the moral.
CHORUS. Faustus is gone: regard his hellish fall,
Whose fiendful fortune may exhort the wise,
Only to wonder at unlawful things,
Whose deepness doth entice such forward wits
To practice more than heavenly power permits.
The antagonism between Faustus and Mephistophilis puts the story on a very human level without causing it to descend into the dark and torturous supernatural. Marlowe's point that there is a divide between the human and the demonic is made clear through this antagonism without, again, resorting to moralizing in the narrative.
As a result, when Faustus reaches his last moments, he hasn't lost his human interest, he hasn't become a type, so we can feel the agony of conflict he is going through and we can urge him, along with the Scholars, to remember his early disregard, throw off the fear of suffering, and act in his own behalf. Thus, Marlowe's most significant thematic point is clearly made: one must act on one's own behalf.
FAUSTUS. Fair Nature's eye, rise, rise again, and make
Perpetual day; or let this hour be but
A year, a month, a week, a natural day,
That Faustus may repent and save his soul!
The stars move still, time runs, the clock will strike,
The devil will come, and Faustus must be damn'd.
O, I'll leap up to my God!—Who pulls me down?—