If you go the AR Decker route, I recommend Encephelon and PuSHeD (can never spell those right) along with some wired reflexes.
I did put together a combat hacker that is pretty mean in a fight, but what would you think about taking a Resonance of 5 and taking an Alphaware Encephalon and the PuSHeD genetic mod on a technomancer? There seem to be a lot of mixed feelings about dropping the Resonance attribute, but going from 6 to 5 does save a lot of points that can be used elsewhere.
Pick up Unwired and check out some of the Echoes and Advanced Echoes available to a Technomancer. Specifically, the Bioware Echo (allowing the TM to use the Resonance to alter his body so that it's a built-in Skillwire), the Sparky Echo (using the Resonance as a touch attack that hampers target's electronics) and the Acceleration (+1 Reaction/IP in the Real World) and Mesh Reality (use Matrix Initiative in Real World, don't go unconscious when in VR) Advanced Echoes. Yes, you can't get them unless you Submerge, but with 500 BP and a flexible GM, you should be able to get at least one Submersion grade at Character Creation.
Don't forget, because everything is wireless, you don't have to sit in the van to hack. You can actually do most of the hacking while in AR, it's just when you go into VR that you get bonuses to hack. My suggestion would be to build the TM with one Submersion grade, take the Bioware and stock up on Active Skillsoft/Complex Forms.
I did look through those echoes, but I'm not sure that my GM will let me start with any of them. Like I said, this'll be his first time running Shadowrun and I don't want to ask him to complicate things any more than he already has. Even still, that's very tempting.
Also, on the skillsofts you learn as complex forms, I know you can't thread them even after they become permanent to raise their rating, and you can't spend karma to improve them, but can you use Edge with them since they are no longer a skillsoft and are now a complex form? I haven't seen anything about that.
You have 500BP to start. See if your DM will allow you to submerge at a cost of 1 BP for 2 Karma. Grab the Biowire echo, and the Acceleration echo a couple times. Suddenly you have 3 IP in the meat as well as the matrix.
Grab a paragon if you like. Alias and Black Hat are favorites of mine. Restricted Gear is a must. Use it to grab a Barret 121. Then get yourself a melee hardened shotgun for close-quarters work. EXEX rounds for both. See where I'm going here?
Biowire allows you to emulate skillsofts you come in contact with, turning them into complex forms. Buy the DocWagon Paramedic and Knight Errant Self-defense skillsoft bundles. If your DM allows, I'd also create one with Longarms and Infiltration.
Get a dummy link, to make people think you're just a hacker on wires. Yes, there aren't witchhunts any more (Clockwork and Mitsuhama notwithstanding), but if you go into an area where they make you check your link at the door, then having a link to turn in (and shutting yourself off from the matrix entirely for a moment) allows you to pass unnoticed.
Any remaining points you don't spend on skills, attributes, forms, sprites, or contacts, use to grab some drones. Yes, you already have a rigger. But there's no reason you can't cover for areas where he's weak. If he has the ground game covered, you take to the air. If he doesn't have aquatic resources, and you're in Seattle, LA, or someplace similar, you might look into it.
Also, and this is just a personal preference, I'd invest in two vehicles. The first is the houseboat from Deadly Waves. When you're spending time probing systems, a mobile base of operations isn't a bad thing. The second is a Bulldog with Chameleon Coating and drone racks. Won't fit in if you're in high society, but for most situations it works, especially if you display private security colors (which also explains why you upped the armor). If you can swing it, you may consider another hit of Restricted Gear to grab a Multilaunch drone rack, and load it up with Dragonflies.
I disagree with others who say Technomancers are specialized. They are the swiss army knives of the matrix.
I meant to say they are more specialized toward Matrix actions than a regular hacker would be without significant Karma expenditures or a Resonance hit. I realize that in the realm of hacking, they are incredibly flexible and valuable.
As for the van, the Rigger has dumped quite a bit into his van already with the idea that I'll be using it as well. I don't know if I can swing the nuyen for my own rigging van.
If the other rigger has ground covered, then you're screwed if you don't want to step on toes in character creation. I've only found a couple vehicles that aren't ground-based (air or water) that are available in creation and at the same time worth getting.
I don't see why a rigger would feel like their toes were being stepped on because someone else brought in more drones. If anything, that makes the rigger stronger because there are now more bodies on the field that he doesn't have to manage.
TBH, from an optimization point of view (not going into roleplaying here) your group doesn't make a lot of sense.
With only 3 players, you can have all the "roles" covered if you all first talk about who'll be doing what.
Rigger/Face doesn't make much sense. Social skills and especially Charisma don't have any use to him. A Cha-based mage or a technomancer can make far more efficient Face characters than a rigger could and would have to spend a lot less resources on it.
Having both a Rigger and a Matrix-specialist in a 3 person group also isn't really that good. Considering the stat and gear requirements and with the charbuild rules you're using, a single Rigger/Hacker character is a far more efficient way to distribute roles.
So Mage/Face, Rigger/Hacker, Combat/Infiltrator seems the best distribution.
That said, I'd like to repeat that this is purely from an optimization point of view. If you're all set the choices you've already made, good for you. I just think that as a 3 person shadowrun team, you might be lacking some things. (Nothing good players and a good GM can't get around, but still...)
I agree that the group is far from optimized, but the guy playing the rigger/face is pretty adamant about doing it. I've tried to explain to him that it would make way more sense for me to take that role as Charisma is actually something a Technomancer needs, but he's totally set on it. The problem is, the programs he took are awesome for, say, drone control, but he didn't take much in the way of heavy hacking programs... lots of Spoof, Sniffer, etc for finding and disrupting enemy drones, but weak on Stealth, Exploit, etc for actual hacking.
The problem is becoming that our group has tons of overlap in the area of face skills, matrix skills, and infiltration skills, but all three of us are weak in actual fighting. I dunno, I hear it said that if it comes down to an actual exchange of bullets, you've already blown your advantage, but it'd be nice to have someone in the group who doesn't just immediately die when that happens.
Thanks everyone for the input, really giving me some stuff to think about!