Of course the 2012 Vuelta's smaller climbs don't make up for the lack of actual difficult climbs. That year the Tour and Vuelta had opposite problems - the Tour had plenty of real mountains but quite a few placed in such a way that they had no impactful, the Vuelta decided to make every climb have an impact, therefore eschewed mid-stage climbs almost entirely.
The Tour has five mountain categories, the Giro and Vuelta only four, so unless they're super early in the race when it starts in places like the Netherlands in the Giro, or the few really small climbs that get cat.3 in the Vuelta (even though they often give cat.1 way too easily), a lot of Tour cat.4 climbs don't get categorization in the other GTs (and indeed if they occur in the second half of the Tour often climbs that would have been cat.4 early in the race to incentivize a battle for the polka dots will just be ignored once the major mountains are taking place).
Anyway, with the Vuelta you get some very random stages. This flat stage includes 5km @ 8% uncategorized before the comienza puerto sign on the cat.3 climb:
Or how about this profile? Plenty of smaller climbs uncategorized here.
Or how's about the 2015 Giro and its stages to Sestri Levante and Imola?
Maybe not flat stages, but that's a LOT of uncategorized climbing.