Where are today's Apostles?
Did the "people in the assembly" vote to "appoint" Paul? If yes, then what constitutes a majority: 51%, 2/3s, unanimity?
Would it be possible to throw the caucus into disarray by letting more or less people assemble?
Peter was simply one of the speakers as were Paul and Barnabas but it was James who made the ultimate decision and statement.
I suppose in a church of one member this could work, but we already know there are four members at least in this church. Why did they listen to James? Is he the smartest, the best debater, did he have the best Powerpoint presentation or what?
These are aBiblical arguments. At every step, God's Church is one of order, not chaos or anarchoChristianity.
We are not told. What difference does it make? It's simply that there was a dispute rising from some who said they had to be circumcised and they didn't think that was right. The simply chose Paul and Barnabas to go back to the apostles and clarify. Trying to inject the understanding developed by the Catholic Church doesn't work.
>>Would it be possible to throw the caucus into disarray by letting more or less people assemble?<<
Again, don't try to inject today's erroneous understanding back into scripture. Whether the assembly their was 10 people or 100 makes no difference.
>>These are Biblical arguments.<<
No, they are not. The questions you are asking exhibits a total misunderstanding of the first century assemblies.