Been running a decker in Missions for a while. I also have the Renraku Tsurugi. I don't have my character or books in front of me, but here is what I do/suggest:
First, modify the stat array to 7 5 5 2. The modification section allows you to modify the array. You are almost never going to need both Attack and Sleaze high at the same time. So, set yourself up at Sleaze 7, Firewall 5, Data Processing 5, and Attack 2. Swap Attack and Firewall when you want to use Attack Actions.
Second, install a Program Carrier modules with Encryption (+1 Firewall). This gives you Sleaze 7, Firewall 6, Data Processing 5, and Attack 2
Programs: Sneak (to protect you from Traces and GOD), ?Exploit? (+1 Sleaze Program), Virtual Machine (you are trying to stay quiet, avoid decking combat), Smoke and Mirrors (running at 1, your datajack negates 1 noise), and whatever other program you use to help what you are doing (this tends to change throughout the run more than any other program). If just sneaking, then Signal Filter and turn your Smoke and Mirrors up to 3. This leaves you with Sleaze 9-11, Firewall 6, Data Processing 5, and Attack 2.
Cyberware/Bioware: Logic Increasing Bioware (can't remember the name), Neocortical Nanos with Soft Nanohive, Limbic Nanos with Soft Nanohive, then Cerebellum Booster. If you are going to AR hack a lot, then Synaptic Booster 2. If you are going to do more VR hacking, I would suggest the cheaper bioware in Chrome Flesh (10,000 and 1 Ess for 1d6 init) or the Synaptic Acceleration geneware (78,000? and 0.4 Ess for 1d6+1 init and 1 defense). The nanos give you 1d and 1 limit to either Logic or Intuition skill checks per level. That won't help you with hiding, but makes you far more likely to make you skill checks. They are, unfortunately, an after character creation purchase due to availability.
I recommend Data Anomaly (purchase after character creation for 6 karma), Overclocker, and Perfect Time (remember that you want your Sleaze to be high on everyone else's turn no matter what you are doing so that you are harder to find). I find this setup works very well, and by being so hard to find I regularly get the job done before the spider/decker/technomancer even finds me. More than once I have taken down an enemy decker/technomancer without ever getting attacked. Don't forget to get 3 marks on the spider, Format Device, and then just check your marks once in a while. If they see that they are marked they will either erase them or reboot to clear them. If they erase them, or see you, then you just reboot device on them and they are out of the fight. Worst case, you need to put some more marks on them.