What's missing?4. Only the melting point of the pure metal is a key issue and the weak point in any metal grid.
Tungsten #1 choice. Molybdenum and Tantalum tied for #2, Hafnium #3 and maybe Titanium #4 as suitable for a real fusor.
Look at the elements with MP's above 2000 degrees C. (Titanium falls far short, almost as much as steel). I proposed carbon in the above-mentioned thread, recognizing its fabrication challenges. And stand in solidarity with Richard Hull in dismissing rhenium, osmium, iridium, and ruthenium -- all generally too expensive and hard.
Prominent in the pruned list is a useful metal called niobium, perhaps overlooked by many fusioneers. Nb has the 7th highest MP of all elements, right behind Mo. It's become popular in jewelry, so Internet searches for "niobium wire" point mostly to earrings and other body-piercing ornaments. It's easily prepared with colorful anodized finishes. I would love to see somebody try a fusor grid made from Nb.
Here is a catalog page with niobium wire in many grid-ish gauges, at around US $17 per one-ounce spool.
http://theringlord.com/cart/shopdisplay ... obium+Wire
There's also an ebay vendor called onyxmetall in Poland, with 2mm Nb wire for $30/meter and 2mm Mo wire for $8/meter.
To close, here's a little demonstration of the metal's excellent formability. I made and am now wearing the thinner ring in this picture. Cold-forged it from a 1/4" long, 3/8" diameter rod of niobium C-103. (Some large artifacts on the Moon are made of the same aerospace alloy, which contains about 10% hafnium.) No cutting tools were used; the piercing was done with a hammer, anvil, and my least favorite center punch. No annealing. That project belongs in yet another thread, along with the zirconium billet in same photo.