I'd first examine the array to ensure that access to the spindles is optimal before working attempting to tweak advanced network configuration values - these are typically fine to be left at default unless you have an edge case that demands an exception (rare).
Raid type, storage grouping, LUN placement, etc. all have great impact on overall performance. This is a good tool for SWAG estimates http://www.wesworld.net/raidcalculator.html