First up, I wanted to chime in on the topic of the Dual-natured. As a Rigger, you could play up the concept of being the dedicated driver and spend a majority of your time in your Rigger-van. The vehicle would block line of sight on the Astral and if you're still attracting astral attention, you probably have bigger problems. I'm not going to go further into that topic than that, I would like to make a big write up with all of the intricacies of what it means to be dual-natured, but this isn't the place, and I haven't put in that time yet.
Someone also mentioned buying your Magic back up, if the dual-natured really feels like a problem for you, then don't. If your Magic attribute hits 0 (and you don't buy it back up) you lose access to all of your Magic-related critter powers. Which for a Sasquatch is Mimicry and Dual-Natured. So you would lose part of your ability to communicate, but it would also eliminate your problem with being dual-natured.
The bigger issue I wanted to bring up was about the Uneducated.
LeVentNoir, your last comment about the Technical skills has me a little confused (based on your wording), but from what I can tell, I think you might have overlooked a bit of the impact the qualities have.
Uneducated doubles the cost of all Technical Active skills (pretty much all of the skills listed on pages 143 - 145), which includes all of the mechanic skills, Hardware, computers, etc. So it probably will affect a fair number of the skills a Rigger cares about (not the direct Pilot ones, but a lot of the supplementary ones.
Uneducated also doubles the cost of all Professional and Academic knowledge skills.
Technical School Education only affects Professional knowledge skills (and even then, only changes the karma costs post-chargen). It also only reduces the cost by 1 for each rank, so normally raising a knowledge skill to rank 4 would cost 4 karma, and Technical School Education bumps that back down to only 3 karma.
So having both, Professional knowledge skills would cost double then back down by 1. So rank 4 would cost 7 instead of 8. If your GM is nice they might let it go the other way (6, but you're still paying 2 more than someone with neither quality).
Now, there is a solution to all of that. It mentions it specifically in the text for Shifters, but Run Faster does talk about being allowed to buy off the Uneducated quality during chargen. I'm guessing you've already worked out with your GM why it would be feasible for a Sasquatch to be a Rigger in the first place, so you probably qualify for the "has a good reason" to be able to buy it off. During chargen you would only pay the karma cost (rather than double) so it would only cost 8 karma to buy it off and just not have to worry about it at all. Probably cheaper in the long run.