Here is what I think. Speed mods should be for pd and special people that need them for specific things. Donating for a faction in my opinion is a shitty perk like you said it is going way out of hand.
Of course, donating for a faction was always the gayest perk ever in my opinion, but anything that helps get the server bill paid shouldn't matter at all until it's abuse. Which in this case that perk is abused alot.