Alakazam takes special hits reasonably well. That said, it comes in against Gengar with impunity and is pretty reasonable against any Water-types... actually making it pretty similar to Raikou in that regard. :P It also switches in against any and all non-attack moves (...except from Jolteon) and is especially good against weak attackers that must rely on those moves, such as Umbreon and Blissey.
None of those switch-ins mentioned are all that dangerous to Alakazam. Starmie is worthless unless it carries T-Wave (who still does that?), Eggy can't really do anything except status/explode (and Stun Spore, the most damning of the bunch, is not a primary option), Forretress must be carrying HP Bug
and hope 'Zam doesn't have Fire Punch. The only "good" switch-ins are Snorlax and Tyranitar, keeping in mind that using Pursuit to trap it is risky. If Alakazam stays in and Encores Pursuit, T-Tar is forced right back out as Recover easily outpaces it.
Sadly, most of Alakazam's best filler moves/attacks are incompatible with Encore (sigh, Seismic Toss...) but it can still carry its elemental punch of choice in that fourth slot. I used to use Fire Punch but, with the wave of new-age douchebags using shit inspired from the newer generations (i.e. using Pursuit at all), I've been using Thunderpunch ever since week 2 SPL when I couldn't kill T-Tar locked into Pursuit (never Burned) and then later it killed me with crit Rock Slide.

It also saves Psychic PP against stupid Suicune, the biggest threat to PP stall besides Raikou/Snorlax. In the land of everything-uses-Rest, running out of Psychic PP is actually the most omnipresent threat for 'Zam, not a particular "counter" coming in to ruin its day.
Eggy can't beat Water pokémon or Tyranitar without Giga Drain. That's significant coverage, making it a perfectly fine option if not the preferred one. The way you shun direct damage you make it sound as if it shouldn't carry Psychic either, which is obviously useful to have around as more than simply "discourages Gengar from predicting Explosion." I'm not discounting the usefulness of Stun Spore (or PAR in general) but you need to do damage to win and Giga Drain puts another ~15% of the metagame on Eggy's hit list. You still have your primary and more important status threat, Sleep Powder.
It's even quite arguable that Giga Drain has better coverage than Psychic... Chew on that little tidbit.