Few things I noticed.
Your using used pistons. Get them sonic cleaned, and then send them out, or have them coated.
Thermal barrier on the crown.
Thermal dispersant on the underside.
Molydisulfied on the skirts.
I don't see a reason for the billet mains, but be my guest. (Are you trying for 1000+hp here?)
Tourqe place installed when they line bore...
and your front cover too, and the larger bolts... (It affects the piston bore more than the line, but everything does move just about everything else around when it's all bolted together.
Head work totally depends on how much you want to spend.
Budget results do not mean poor results
Comp Cams springs, and larger valves if you can find them. (Guy named enginebuilder on eBay was my source for stainless ones, 1mm over sized... Work fine, and included new bronze valve guides in the deal, about 225.00 shipped IIRC.)
There are plenty of posts on this stuff however...
After building a few of these, I've often wondered if just spending about the same amount of money on a nice 7.0L twin turbo V8 would be less hassle, and result in way more power, and less chance for failure?
Then again, I'd probably be sent straight to Toyota Hell when I die....
LOL