Yeah, that's a typo. (One I missed no less, I'll get that flagged for you.) As the only reference in the PDF to increased Essence costs for improved Amps I think it's safe to say it's a hold-over from editing. Way too much bookkeeping for Anarchy
You are correct about the Cyberspurs. +1AMP for "Advanced Effect" & no additional Essence cost.
A hard limit to the number of things you can cram into ware could help. Then again the text boxes aren't *that* big. Once you have 3 different bonuses on one Amp do you really need any more?
P.s. If you have a Port/Build-a-Ware request or want to double-check your maths, feel free. Finally living the legit Implanted RCC dream. Stick it Cyberdecks