I wanna get rid of my entire bone skeleton and replace it with a motor-powered carbon-reinforced nano bones. The motors will be off most of the time, but whenever I need to lift a car or something, I could mind-switch to motors. If they are strong enough – and I get a reinforced skull – I can safely jump off buildings. And the new rib cage will come in handy when I am getting shot. I will be invincible to bullets, falls, and most car crashes.
I want an implanted OpenBSD computer interfacing directly with my brain. That way I can post on TrekBBS how implants are ridiculous and a slippery slope towards the end of humanity while I am walking to work. As long as I resist the urge to click on links to erotic websites, I see no downsides. My reinforced carbon skeleton will ensure that I will be alive after any vining-while-crossing crash. I am sure I can wirelessly interface with any doors in the vicinity, and in-head Wikipedia means that I can tell call people stupid in real life too. Both can be dangerous if I am not bulletproof.
Out of the extras, one could never go wrong with self-cleaning teeth. Lack of self-cleaning teeth is probably the single most severe problem facing humanity today, only second to the new autoplay feature on YouTube. Also getting human waste to get out inside impermeable biodegradable bags can home in handy. I am looking forward to that.
ETA: Bonus: Inter-mind communication. It has been observed in conjoined twins, so I don't see why I shouldn't be able to do it wirelessly. Not that is crazy enough to consent to inter-mind me.