Easiest, most efficient, and most optimized to make an adept for a stealthy shotgun biker. Can bill as an infiltrator and muscle pretty easily. Improved Reflexes is going to go a long way in being a good biker. EABCD comes to mind for a pure adept... AEDCB or AEDBC elf/dwarf can swing it for a 'wared adept...
A full magician will be tempted to take more full magey stuff to be the magical specialist of a team. I would suggest getting some of the fun vehicle spells and road manipulation spells as part of the character. ECABD will get you a bike and starting gear, the skills to be good enough at what you want to be good at and a good team magic specialist, and the spells/spirits to help you be better at those things (increase reflexes and a health sustaining focus will prob be part of this repertoire).
I prefer an aspected conjurer. AEDBC Elf or Dwarf (or ork) will get you a highish edge Magic 4 or 5 aspected magician (with an essence point or two of 'ware) that can summon/bind (but doesn't have super high Charisma to be obnoxious with a giant bound spirit herd), shoot a shotgun, bike, be sneaky, and have other basic runner skills, and still have the cash for a nice bike and some foci at chargen. A character like this is more of a generalist (can shoot, drive, sneak, and conjure, but not top tier at any of them), but depending on the kind of table you are playing with (this character is more appropriate for a more sandbox game than strictly going from one run to the next game) a character like this can be a lot of fun.
You may not sneak/bike as well as an adept, you can still bring a bunch of spirit utility to the table.
I also think that thematically being an aspected magician is more in line with spending a lot of time as a go-ganger.
Generally, putting skill groups into conjuring is not recommended because banishing is a poorly designed skill that is often avoided. (If you can conjure spirits, it is almost always better to summon a spirit to fight another spirit than it is to try to banish that spirit). If you plan on binding spirits, you are going to want to max/spec binding at chargen. If you are really short on skill points, you can usually skimp a little on summoning, but as spirits scale in power very steeply, being able to summon bigger spirits with more services more consistently tends to be a very good investment (so max/spec summoning if you can too). Qualities/mentors/foci also help.
