FIV: The car will idle rougher in the cold, this can be adjust by the idle screw. If you do that, eliminate the coolant lines to and from the FIV. Your IAC (intake air charge will be a few degress cooler)

IACV? Idle Air Control Valve. Controls how the car idles by letting additional air into the IM rather than through the TB. Its not necessary either, you can block it off and remove coolant lines there as well, the car will idle rougher overall (flucuate a few 10's of rpms) but thats about it.

If you live somewhere freeeeezing cold for mutliple months in the year, just diassemble those pieces, screw the spring down on the wax plug and it'll be temporarily fixed.