1) You take exceptional attribute (Willpower), and you start at 7
2) You put 5 in logic & intuition
You already have pretty decent Living Persona. Your attack rating probably won't be great, but it works. And, you still can have 4 in reaction & intution, 3 in body and 2 in strength. Which leaves some room to be decent at something else.
Then, after some time, you buy a cerebral booster 3 and a cerebellum booster 2. You can reach (as a human) 9 logic, 8 intuition, 7 willpower (and 6 charisma if you really want that attack score). All of that, for the cost of 43 karma needed to raise your Resonance back to 6, including a submersion. And that's not even taking drugs into account, a simple Psyche will then get you to 10 logic, 9 intuition. You're not likely to find a deck that good anytime soon. Even the Excalibur is at 9/8/7/6. It takes some time and karma, but a TM can beat that.
So while I'll agree that not being able to have a PAN can be bothersome (and I wont go so far as saying it's the first role of the hacker in a group...), that having to take some bioware to be efficient kinda goes against the lore, you still have a lot of possibilities to be good at hacking and at other stuff. Not as straightforward as the decker, but it exists. And the technomancer has access to stuff the decker can only dream about (like the Resonance Realms for instance, some of the CF, and the sprites of course).
So no, TM are perfectible, but they already are a valid option. Just not as brainless as a decker can be, you have to think, anticipate and plan how you do things, that's all.