ok just got a 420 rad up top and a 280 rad in the bot got a mcp 655 pump and a dual bay res so should my loop go
res pump cpu rad gpu gpu rad res or
res pump rad cpu gpu gpu rad res
running to 560 ti 448 core and a i5 2500k
Loop order is mostly irrelevant to be honest with you, the only 'fixed' point is,
its generally accepted to have the pump straight after the res (if pump isn't actually in your res) which you have outlined in both scenarios there anyway,
a lot of people think that having a rad after a block helps cool the water some before hitting the next block,
truth be told,
it takes a certain amount of time for all the liquid in the loop to reach a balance with temps, might be 15 minutes, might be an hour depending on the size/volume of your loop, but once its settled, its settled and you won't find more than a few degrees difference in temps at any point in the loop (insane methods notwithstanding ofc)
build the loop as you see fit, for tidy tubing or shortest/easiest routing, or hide them all
it really does not make a deal of difference
Loop order does not matter, as Moto mentioned. Having your reservoir outlet feed your pump inlet while also being higher in your case does help with filling and bleeding of air. This isn't a cardinal rule, but it's a very common practice among the watercooling community, myself included.
Water is flowing quite fast through your loop and it never gets hot. In fact, it should never really get to lukewarm, but this is dependent on your loop's delta-T, which is covered in the watercooling sticky.