As a christian, how did you handle the problems with the Tower of Babel?

[Drich]

So said god as told to DRICH. We call this SPAG. It means "self projection as god."

Let me correct your statement:
So God told DRICH. (Through the bible) We call this READING, What Is On Page without Adding Commentary.

In the NIV version:
5 But the Lord came down to see the city and the tower the people were building. 6 The Lord said, “If as one people speaking the same language they have begun to do this, then nothing they plan to do will be impossible for them. 7 Come, let us go down and confuse their language so they will not understand each other.”

Again you have added the commentary. No where even in you perferred version does it say God was worried that they would make it to Heaven. It simply shows a concern God had for the collabertive effort these men would accomplish. (Verse 6 spell the whole thing out for you)

Now if you take what was written and THEN look at what is known now, one can see God was not worried about man building a physical tower to heaven, as 'Heaven" is not a city in the clouds. That forced a thinking mind to stay with in the context of the story itself. In that God's concern was about the collaberation of Man. (As the either account states)

If a bunch of kids were trying to build a tower to reach up onto your roof, and you did something to scuttle their plans by splitting them up and then said that " I had to split these kids apart because together they can accomplish anything they set their sight to", then it is obvious to any non brain dead member of the human race that you were referring to the kids being able to have reached their original objective.

Ah, no. "Accomplishing anything in their sight" refers to far larger and more ambishious projects than a tower that could not exceed 10,000 ft.
Any "projects" that go outside the plan of salvation God has gets 'corrected.' Why do you think God had Israel destroy so many different people?

Furthermore, god came down from the heavens, which by the way, is the opposite direction the tower was going up. This also leads credence to the bible author believing that heaven was in the sky and the target for the tower.

So?

Why does god use the plural form here? why does he say "Come, let us go down?"

God the Father, God the Son God the Holy Spirit, or any combination of the three. All three or Combination meaning more than one hence the plural form.

I wasn't aware that there was a set speed for mankind's development. Do you have any reference for this

Yes!
Genesis 11: 1-9