No. Generally the more you spread out, the weaker you get overall unless you have a really good handle on the system.
The first thing you need to do is figure out what kind of magic you're wanting to actually do.
Adepts have, for the most part, passive magic that just enhances their abilities. Think of it like magic steroids or, in more gamer oriented terms, super mario growth mushrooms. The power is there, but you don't have to do much to get it to work and it's fairly simple.
Mages have active magic that is fairly complicated. The spells vary depending on what you choose, but you always have to choose a force to cast at and resist drain. These are things like you traditional lighting bolt or, again in more gamer oriented terms, super mario fireball flowers. You have to do something to use the power.
Mystic Adepts are a combination of the two that are either A.) wonderful or B.) about as effective as slapping the badguys with a pool noodle, depending of course on how your GM runs them (the book and FAQ contradict each other in a very major way concerning how mystic adepts work).
Now, there is also cyberware. Cyberware and Bioware (I usually refer to both as cyberware because back when I started playing cyberware was what all augmentations were) enhance your abilities, but hurt your magical abilities. That said, some ware is a good trade off. The key is in efficiency which means you start with a little and upgrade it to more essence friendly options in game to get more without continuing to eat your essence.
This sounds like a lot, but the key here is that if you just want to make a guy that can sneak, stab/shoot, and throw fireballs, you have a lot of options. You can make an augmented mage (just a mage with bio/cyber to boost your sneaky/weapons abilities), you can make a mystic adept (split your magic between magic steroids and spells), or you can make an Augmented Mystic Adept. Keep in mind that your magic is not going to start as high as a straight mage's will in any of these cases.
Then again, you can also just make a combat mage and use non-cyber bonuses to help your stealth abilities and weapon foci for stabbing things. Mage's can get spells like silence, stealth and Imp. Invisibilitiy which really help for those Syphon Filter/Splinter Cell style runs.