When trying to figure this out, I find that the Greek word in Luke is the same word used in Mathew 23. However, depending on the translator, it is translated differently. A translator's theology does affect the chosen word, I believe.
1787 [e] entos ἐντὸς : It is interesting that this same Greek word has been translated differently in the same bible. For example, in the KJV it is translated "within" for Luke 17 but is translated "that within" in Matt 23. The NAS translates it "the inside" in Matt 23 but "in your midst" in Luke. The interlinear bible translates it "inside" for Matt but "in the midst" for Luke. Different meanings for the exact same Greek word.
Then again, I believe that all scripture passages regarding a topic must support each other in order to determine truth. It is very hard to do without close examination. I think God intended for us to seek what we can and then wait on Him to give the truth to us. While I wait, I reference other passages.
It seems to me that it gets confusing to think that the dwelling of the Spirit within the children of God on earth does not comprise His kingdom on earth. A kingdom without a castle (for God does not live in a building) is here now, but not yet.
While believers are indwelt and walking according to the commands of the King while on this earth, there will come a time when the Kingdom is visible to everyone.
Mk 1:14–15 Now after John was arrested, Jesus came into Galilee, proclaiming the gospel of God, and saying, “The time is fulfilled, and the kingdom of God is at hand; repent and believe in the gospel.”
We may question what it means when Yeshua said the kingdom of God is at hand (or has drawn near). But then again, we read:
Mt 16:28 Truly, I say to you, there are some standing here who will not taste death until they see the Son of Man coming in his kingdom.”
Now, both of the passages have to coincide to make truth.
Another passage may illustrate how the kingdom is now buy not yet:
John 18:36-37 Jesus answered, “My kingdom is not of this world. If my kingdom were of this world, my servants would have been fighting, that I might not be delivered over to the Jews. But my kingdom is not from the world.” Then Pilate said to him, “So you are a king?” Jesus answered, “You say that I am a king. For this purpose I was born and for this purpose I have come into the world—to bear witness to the truth. Everyone who is of the truth listens to my voice.”
As difficult as it may be to see Yahweh's truth here, I know who right now who is my King.
How do you all see it?