I like the Little Hornet from Data Trails, but I don't mind the micromanaging and I don't take the Cybercombat skill so I'm never trying to juggle 4 stats, usually just leave the second highest in Firewall, Highest in Sleaze, and bounce the Sleaze and Data Processing around depending on the action I'm doing that turn. Attack gets a 1, if I need to crack file protection I'll swap into Attack, but that is really the only time. The Second highest number just always stays in Firewall.
The 300, IMO, is a lot of Deck. Especially with Overclocker, programs, and Perfect Time. You're going to be over 500 Karma into the game before your dice pools get big enough to need to upgrade. Probably more if you're fixing stats and branching out your skills at all.
And also, Smoke and Mirrors is essentially, broken. You can easily pick up a +5 Sleaze and cancel out the noise with Antenna and Datajacks. That is really the key to making the low end decks function. With Overclocker, Stealth, Smoke and Mirrors, you've got a +7 to Sleaze potentially. It's why you can get away with hacking on a Commlink with a dongle. Your opposed checks are typically Sleaze, the Data Processing tests are typically a threshold (couple key exceptions). And the one Attack test I ever would use is a Threshold. IMO, Firewall is your second line of Defense, you should be running silent and have a lot of dice to avoid detection.