I agree that we must take these accounts into view. Out of all the people in Acts who were folded into the church there are only 3 instances where speaking in tongues is linked to the believer. And these three instances have purposes, in Acts 2 it was, as stated above, for the people who hear the message in their language. In fact, that is more amazing that that the apostles were speaking a language. 3,000 people and they all heard their language, that was a gift of hearing on top of the languages spoken.
To step to the side I think it is important to remember this "tongue" was a REAL language spoken, what unknown meant was that it was "unlearned" by the apostles.
The second instance, Acts 10, was for the purpose of spreading the gospel to the gentiles. Peter had a group of Jews with him when the gentiles began speaking in tongues, then Acts 11 Peter tells the Jewish council that, "the Spirit came upon them as it did on us in the beginning." Hence a distinct purpose to that outpouring of the Spirit.
The final instance was with Paul in Acts 19 and was for the purpose of showing that the God they were praching was powerful. They were doing unusual miracles because the people their were into "witch craft", similar to what Moses dealt with in Egypt.
I think balancing this with the usage in Corinthians is important because it takes the emphasis off the gift and on the one who is behind it. God acts for his Glory and His name's sake, we see these gifts and should be in turn looking to the one who can give us far more joy and peace.