I've been thinking about this, and I don't think these names are too bad actually. Because if you think about it, Irrational functions truly lead the individual to become, on the deepest level, irrational thinkers, and the same goes for Rational functions. Seriously, look at Se. Where's the logic of territorial acquisition? There isn't any; it's a base motivation; an animal instinct; a passion. Okay, the SEE or the SLE may act rationally, but they're fuelled primarily by their Irrational function. The same can be said of ILIs; these individuals look rational on the outside, but they're fuelled by an undoubtedly Irrational function; one of mysticism and of little reason whatsoever; what makes them reasonable people is their Te creative blocked with their Ni base. But take an unhealthy Irrational, and they sure as shit are irrational people. This might be hard for a lot of you to accept, but hopefully you'll find it consolling that, as an Irrational myself, I'm not propelling some Rational dogma; this is what I actually think.
Rational base functions will always encourage the individual to act rationally most of the time (when their creative Irrational function isn't interfering). Some might argue that Fe and Fi are hardly Rational functions, but think about it. They're simply a different code to Te and Ti Rationality, which is stereotypically Rational. They're Rational because they're based on feelings which are moralistically rational, as opposed to logical and rational in the every day meaning of the word.