savmagoett said:

you can see below a 150 m Tantive as portrayed above:

What do you think guys?

This seems too big to me. I may be totally wrong, but it seems like all the composite shots are too inconsistent to be relied on that heavily. Another possibility may be to try to judge the size of the ship based on the interior corridors. The droids are a consistent size as are the escape pods and the spacing of the pod hatches in the ship. I don't know if that approach would be helpful or not.