5/8" line?

i am in the process of completely redoing my set up on a '86 b2000. i had 4 3/8" block valves, half inch lines, 2 6 gallon tanks, 2 4' nitrogen tanks and some Generic 1/2" 2500 bags.

i just picked up 8 1/2" blitluft (spelling) nockoff valves. i got them in trade. i am getting rid of the compressors and just running nitrogen. while i have it all out i want to know if it will be worth running bigger line. i want to know before i order some new 300 psi bags. what are the advantages, if any, to running bigger line. i dont mind wasting some air. i just want it the best now so im not redoing it again next winter. im also worried that the valves wont hold up to that kind fo pressure.

any input is greatly appreciated.