~~ Bead stringing material :
Most discussions re 'the best' bead stringing material seem to conclude that SoftFlex --- one of several brands of fine-woven-stainless-steel-cable beading wires --- gives the prettiest & most elegant-looking 'drape' ... along with being very easy to use, resistant to breakage, very longlasting, and even 'knottable' if absolutely necessary.
It's also fairly expensive, but then so are some other brands in this type of beading wire (such as AccuFlex Platinum). Everyone I know who uses SoftFlex says 'well worth every penny' and most people who switch to it never go back to whatever else they were using.
I believe softFlex comes in a color called Silver Satin and also in a color called 24k gold. It would be best to see the products & read the info/ recommendations *at the SoftFlex manufacturer's website* but at the moment I can;t seem to find it.
Anyway, you can see some prices & the two colors here :http://www.artbeads.com/stringing-materials-soft-flex.htmlhttp://www.artbeads.com/stringing-materials-soft-flex-gold.html
For the finest 'look' as well as for best durability of the piece --- don't use a beading wire in a diameter so thin and fine that your beads have a lot of 'play' and slide loosely all over the beading wire.
However, of course you don't want to have to *yank* the beading wire through the beads either.
Best compromise is to use the beading wire diameter that most nearly fits all the different sizes & meterials of beads you'll be using for the piece.
~~ Findings (such things as clasps, headpins, crimp tubes, French bullion [if used], etc ) :
I rather doubt any beadstringer would disagree that the best would be solid 14k gold. These days that's often prohibitively expensive though -- so next best choices in gold would be gold-filled (not gold plated) or vermeil which is 18k to 24k gold bonded over sterling silver.
Of course sterling silver is lovely too, although it does need a bit more care than gold because it's always wanting to tarnish, lol.
One of the MOST important things you can do to make a beautiful but also a strong durable piece is to use ONLY sterling or gold-filled or gold CRIMP TUBES (not the round crimp beads) and make sure they're the correct size for the diameter of your beading wire.
Also -- many beaders say using the specially-made CRIMP TOOL in the correct way is also very important --- as opposed to just smashing the crimp tube with a regular pair of pliers. A properly crimped tube looks much more professional and lasts better too.
It's also a good idea to string one 2.5mm to 3 mm 'buffer' bead on each side of each crimp tube. Buffer beads are most often just plain small round sterling, GF, or gold. They help relieve stress where it can weaken a piece most ::: near the clasp parts and near any crimped tube.
If your piece involves loops of beading wire at each clasp end -- which some people don't like the looks of -- you can use French bullion (aka French coil) in silver or gold and in the appropriate size for your beading wire. Makes the beading wire loop look like a solid metal loop, gives a nice professional touch, and also helps protect the loops of beading wire from wear or breakage at the clasp -- that's often "yet another" potential stress point.
Hope that addressed some of your concerns.