I recently like the idea of Apprentice with Dedicated Conjurer, specifically, gaining a spirit of Man to cast the spells your "know". This let's you put a really low emphasis on Magic, which means you can do a secondary or primary role quite nicely I noticed. Slap on spirit whisperer quality, for even higher force, for things like analyze device on a 'deck'.
Not that its more 'powerful' but Buddhist (alt) gives you barehanded adept for free along with spirit pilgrim/lodge. Depending on the rules, you can actually get a tradition as an adept, so its nice free qualities for one. OR you can use on the apprentice or aspected conjurer version above to gain a few more touch spells, but it does become costly due to the loss of reagents and thus binding. Can still pick up chain breaker tho on top of this for +5 total spirits. Also recommended for synergy is traveler lifestyle + Bat mentor because unlike other mages, you aren't setting up lodges.
Dedicated Conjurer/Chain Breaker both don't list spirit types unlike the UMT initiation later... This could mean you can gain "any spirit" aka "shadow, etc." Personally love the idea you could have a succubus at chargen then that could work as distraction, your face, etc, but most GMs would probably frown on this.
Possession mages with vehicles become a bit more viable after Dedicated conjurer, Archivist, Chain breaker, Spirit Whisperer, etc all come into the mix. Assuming you GM is (in)sane, and the objects get 15 dice to resist or less, then having a Force 8+ can easily be done with stun drain only, and then be inside the vehicle/drone for that real magic + tech merging.
Adepts with barehanded adept (possibly from Buddhist Tradition alt following above) and adept spell (shapechange) can easily start with 3 body, flesh sculptor, and one of their touch spells as increase body. This let's them have the whole of the animal kingdom eventually, along with Athlete's Way for Supernatural Prowess. Plus many of the adept powers like Kiai can be a "bark/howl", voice control allows 'speech', nimble fingers despite a sanity check against it, allows for free action readying/grabbing of items. YMMV, but its not more 'powerful' but a way to get shapechange viable on an adept.
Skills A characters with Spider (Alt) mentor can get 6 group in stealth, and 6 group in something else. Oddly enough, this can be combined with the above, to gain a very wide character at chargen that has a 'combat/infiltration' option of shapechange.
Anyway, that's all I got, hope that helps!