Yes, is there any reason the Woman of Revelations can't symbolize both the Theotokos and Israel?
There is an old tradition that says the Mother of God did not experience pain when she gave birth to Christ. I'm pretty sure this is a tradition of both the OO and EO Churches. I assume the Catholics have the same tradition, but I could be wrong. The woman in Revealtion 12 was experiencing pain in childbirth, so she therefore can't be the Mother of God. Or so I have been told.
More than Tradition, it is Prophecy:
1 Thus says the LORD: "Heaven is my throne and the earth is my footstool; what is the house which you would build for me, and what is the place of my rest? 2 All these things my hand has made, and so all these things are mine, says the LORD. But this is the man to whom I will look, he that is humble and contrite in spirit, and trembles at my word. 3 "He who slaughters an ox is like him who kills a man; he who sacrifices a lamb, like him who breaks a dog's neck; he who presents a cereal offering, like him who offers swine's blood; he who makes a memorial offering of frankincense, like him who blesses an idol. These have chosen their own ways, and their soul delights in their abominations; 4 I also will choose affliction for them, and bring their fears upon them; because, when I called, no one answered, when I spoke they did not listen; but they did what was evil in my eyes, and chose that in which I did not delight." 5 Hear the word of the LORD, you who tremble at his word: "Your brethren who hate you and cast you out for my name's sake have said, 'Let the LORD be glorified, that we may see your joy'; but it is they who shall be put to shame. 6 "Hark, an uproar from the city! A voice from the temple! The voice of the LORD, rendering recompense to his enemies! 7 "Before she was in labor she gave birth; before her pain came upon her she was delivered of a son. 8 Who has heard such a thing? Who has seen such things
? Shall a land be born in one day? Shall a nation be brought forth in one moment? For as soon as Zion was in labor she brought forth her sons. 9 Shall I bring to the birth and not cause to bring forth? says the LORD; shall I, who cause to bring forth, shut the womb? says your God. 10 "Rejoice with Jerusalem, and be glad for her, all you who love her; rejoice with her in joy, all you who mourn over her; 11 that you may suck and be satisfied with her consoling breasts; that you may drink deeply with delight from the abundance of her glory." 12 For thus says the LORD: "Behold, I will extend prosperity to her like a river, and the wealth of the nations like an overflowing stream; and you shall suck, you shall be carried upon her hip, and dandled upon her knees. 13 As one whom his mother comforts, so I will comfort you; you shall be comforted in Jerusalem. 14 You shall see, and your heart shall rejoice; your bones shall flourish like the grass; and it shall be known that the hand of the LORD is with his servants, and his indignation is against his enemies.