That was a problem, yes - spells all cost the same, and things like Fashion (cleans your clothes) and Healthy Glow (makes you look healthy) were listed alongside Heal (actually makes you healthy) and Alter Memory (exactly what it says). However, foci really weren't a big deal; though.
Ah, but while those spells were listed 'together', they still had different costs. It might take the same amount of work to figure out each spell, but a person could cast that Healthy Glow a dozen times a day without a problem, while the magi-doc would be exhausted after treating two or three wounds at most, depending on how they were built. That Healthy Glow allows your mage to make the entire team look fit-as-a-fiddle, which can let you bluff your way past a number of issues. There's also the (in game) legality of spells; if you don't have a 'license' for an Alter Memory spell and you get caught with the grimoire or using it (if wherever you are even allows people to get registered to use that kind of spell), and you're going to have a bad day. You can have all the Fashion spells you want however, which work quite well for the clothing portion of a disguise. Making that set of body-armor look like a nice suit and tie is very useful if used properly as well. (By the way, the costs of the spell formula are different; it's only the karma cost that stays the same.)
Shadowrun is big on the 'use things the way they are needed, not the way they are designed', from my perspective. If you want to take the time and use the effort and spend the resources to design your own spells? Good on you! If you're a bargain bin rummaging shaman with a tight budget and a rumbling stomach, you might just go buy a pirated copy of one of those beautician spells so you can actually eat for the next two weeks, since it'll get the job done if you use it right and it won't get corp-sec or the Lone Star on your tail.
That same mindset applies to foci as well. That Rating 1 Sustaining Focus isn't going to do much... Except maybe support an Oxygenate spell so you can go diving or survive in a room pumped full of some kind of gas or carbon monoxide. Or, if you're a vampire/banshee, it'll keep you from going dormant without air, letting you escape before the hunters take you out while unconscious. A Power Focus is pretty superfluous in that same situation, but if you're slinging spell-fire, it helps a lot. Weapon foci are awesome... If you're in a fight. Otherwise, they hamper sneaking as bright astral beacons, and for generally being things like swords, spears, big ole daggers, etc.
I can't say much on possession spirits, since the games I've been in haven't really used them much, except for insect spirits/shedim bad-guys (and they have their own rules).
... If you can't guess, I'm a big (huge) fan of Shadowrun. Hands-down my favorite RPG setting by a wide margin (as a setting designed for RPGs, the Dresden Files is about tied in the novel-based category).
Something else I like to add, in regards to Shadowrun, is the interaction between technology and magic. They are not pretty interactions, which I love, and they make hexing in the Dresden Files look sort of fluffy in comparison. Let's see...
1. Cyberware/bioware disrupts the connection between body and soul; if you get enough of it, you pretty much spontaneously die, your soul slipping away from the weakened body. (This can have negative effects on a person's magical capabilities.)
2. Except for cyberzombies. Using various kinds of magic (generally of the dark or corrupt blood-powered kind), you can bind the soul to the body, allowing you to stuff more technology into the body, making them into a superb killing machine! Sounds great, until you realize that the body starts growing tumors and develops other maladies almost constantly, various mental health issues develop and can cascade into gibbering violent psychosis due to the fact that your body knows it should be dead and thus keeps trying to throw the kill-switch, the cyberzombie creates a constant magical drain-effect/death field/blight around them, which kills small plants and animals and grows the longer the cyberzombie remains in the area, and if the ritual isn't done properly, their body might just be possessed by some kind of horror that will slaughter everyone it can get to.
3. When a corporation tried to design a gun that would be able to shoot magical bullets, then entire design pretty much got hexed from then on, even when they stopped that part of the project. The gun would make the ammo in the magazine explode, drop the mags when you try to load it, split the barrel, have inexplicable glitches in the generally reliable smartgun software, etc.
4. The anti-dragon bio-weapon (Blue 227, if I remember correctly) another corporation developed appears to have worked (even if the dragon they used it on still survived, he was hurt
bad)! It also appears to drive people insane when exposed to small amounts carried thousands of miles away by the wind.
5. Exposure to pollution-blighted areas can have negative effects on magic-users, eventually turning them into psychotic and/or sociopathic toxic shamans, whose goals range from ravaging the environment to killing all of humanity to blowing up the entire planet with nuclear weapons.
6. Another bio-weapon developed, a form of bacteria that devours magical energies, went native in an environment they released it and killed hundreds of people by floating around in clouds and devouring their magic until they died or escaped. It still haunts the area, ruining the magic in the area and trying to eat people when possible.
The list goes on if you dig a bit, but... Oh, it's awesome. I've been jonesing for more Shadowrun for a while now, since my TT game is on hiatus for the moment.