Ramp in white feels just completely wrong to me. Like lifegain in red.
		
		
	 
You can justify pretty much anything with flavour if you try hard enough.
White counterspells are just an example of white saying, "no, get back in line". Taxing effects like 
Mana Tithe are just that - a tax. 
Lapse of Certainty effects are bureaucracy. A hypothetical white 
Cancel would be an Azorius enforcer laying down the law.
White ramp, we actually have some examples of this in recent times, such as 
Deep Gnome Terramancer. It enforces a sense of fairness, the equivalent of the teacher asking if you brought enough gum for the whole class. You got ramp? Shouldn't you be sharing that? Even pure white ramp like a hypothetical white 
Rampant Growth that fetches Plains could be society banding together for the greater good, or imperialistic conquest.
Red lifegain is invigoration; bloodlust, passion, fighting through pain. Normally this is represented with power/toughness boosts, but that's just for creatures; how about the red mage themselves? You can't keep me down! I'm just having 
Illusions of Grandeur, you say? Who cares what you think?!