Well if Paul is to be believed then "to be absent of the body is to be present with the Lord" and as Jesus said on the Cross "today we will be in paradise", this seems to imply an immediate existence in heaven for at least Christians.
You're using parts of sentences out of context, and sticking with traditional punctuation that was only inserted a few centuries ago. (Punctuation marks had not been invented yet when the bible was written.)
It is just as valid to interpret Luke 23:43 as "And he said to him, 'Truly
, I say to you today, you shall be with me in paradise.'"
Scripture does not actually say "to be absent of the body is to be present with the Lord," but "We know that while we are at home in the body we are away from the Lord, [SUP]7[/SUP]for we walk by faith, not by sight. [SUP]8[/SUP]Yes, we are of good courage, and
we would rather be away from the body
and at home with the Lord." In the part you (mis)quoted he was stating a desire for the two conditions, not unequivocally equating them. As more accurate translations don't just speak of being in the body but of being
at home in the body, it might imply a degree of comfort in our current unperfected state. Being way from the body could also mean being away from our
current bodies, but in our glorified bodies in the presence of God after the resurrection. When you look at the broader context of 2 Corinthians 5 you see that as a whole it strongly supports the doctrine of the bodily resurrection. Verse 4 makes it clear that while we may be burdened by our current mortal bodies we do to wish to be naked without a body but rather to be further clothed in our future incorruptible bodies. The word traditionally translated "eternal" in the first verse actually means "of [the next] age," implying a time in the distant future rather than immediate.
2 Peter 3:16 warns that in his letters Paul speaks of things that are very hard to understand which the unlearned often twist into destructive interpretations. (Originally I thinking this was in Acts, and was disappointed to find it is was 2 Peter as most modern scholarship supports the notion that the epistles 2 Peter and Jude are 2nd century forgeries.)
Ecclesiastes is pretty clear that there is no activity, planning, knowledge, or wisdom in the grave (sheol), which argues against consciousness surviving death but against it being restored in the resurrection of the coming age.