marti, I've looked at your part... there's still a lot of space left. 5 blocks in front of the end and 6 blocks to the left. The problem is that people can't really make a right turn because of all the scenery there. But they'll deal with it.
I think it would be foolish to change the rule at this point since people have already been building their stage 4 parts and some have already been uploaded. It'd give others an advantage that those first uploaders didn't have.
We could possibly see a change in the rules for stage 5, but I guess we'll first see what we end up with at the end of stage 4. Obviously for "official" word on it, we wait for KekX.