In my humble opinion:

1.0 Pipe tone vs. materials of construction:

I argue that the same pipe design executed in various woods all sound
the same.  I have built wooden chimney-flutes, bourdons, and violin
pipes using pear wood, orange wood, sugar maple, and alpine spruce.
For a given pipe design and note I cannot hear a difference between
each of these woods on a wind table once the pipe is voiced.

I argue that for metal pipes, harder alloys make brighter sounding
flute pipes.  I have built flutes with 90% tin/10% lead and
80% lead/20% tin (don't ask how - it's hard to believe).  The higher
tin content pipes were definitely brighter for a given design.

2.0 Imitative pipe names:

Organ pipes with names the same as orchestral instruments are just that
and no more.  They do not sound like the instruments named.  Trumpets,
violins, trombones, tubas, flutes, clarinets, bassoons, cellos and the
like never sound like their orchestral counterpart.  The rough
suggestion of reeds or flues or strings or brass is there but they
really sound like organ pipes and not orchestral instruments.  This is
why theater organs sound like theater organs and not like orchestras.

3.0 Adaptation of old organ pipes for band organ use:

Don't do it.  Used organ pipes are generally in sad shape.  Also, pipes
are generally designed for a given wind pressure.  Unless all the pipes
came from the same organ there's a good chance that each rank will
require a different wind pressure.  Buy new pipes or build your own
(not as hard as you might think) if you can find some design specs or
plans.

4.0 Pipe tone vs. wind pressure:

Pipes that speak with a higher wind pressure (25") are brighter
sounding than pipes that speak with a lower wind pressure (2.5").
This is because of variation in mouth or reed design variations
necessary to achieve speech vs. wind pressure.  This is not due to wind
pressure itself.

5.0 Argue with me if I'm wrong.

Like it says.

Bill Finch