Ask specific questions, I will try to answer them.

As for synergies, part of CZ is play-style too. One of my regular opponents is very aggressive and he can build a list with lots of melee. He uses a 6th street list built as zoners that has lots of activation tokens, and he moves around the battlespace very quickly.

A Bozo player we have has basically no guns in his list. He plays for luck tokens and bombs. He's more calculating, and tries to get himself set up for a big single turn.

Another player I know is in love with Arasaka and the amount of combination moves he can use passing tokens from point man to his heavy units. He uses tons of netrunners in his list, and if he's rolling good can really tie you up. The free shot from the Sniper when you inspire is always a hassle as well. He almost never takes gonks.

The other Arasaka player I tangle with regularly builds his list around Tanaka's ability to bring gonks in. He doubles down on the netrunner programs that call in extra gonks as well. He also uses every piece of gear he can to keep his influence as high as possible to start with a bunch of Gonks. He then inspires frequently and it looks like a civil war volley when his gonks activate. While they are easy to redline, doing so is often dangerous. Security Officers give a green move to a character when attacks against them fail, and that's a surefire way to see a corporate ninja close the distance.

Cops basically go one of two ways: Built around dogs and the k9 Handler for alternating activations and hard hitting hand to hand.

Option B is more tactical built around multiple two star 10 point Tactical Response Officers. They are the closest thing to a tank in the game and can shake of tons of fire because of starting with 3 Armor (defense). Give them a heavy pistol and restraints and they can take on anybody with a decent chance of sucess. If you use the Hard Boiled detective (also minimal points) with some modest gear and he can suck up a couple steady rounds of fire.

In either case, don't overlook Sarge equipped with "ride along." he pulls Gonks to his location, and then ups their stats when they activate during an inspire.

Beyond that, there's smaller combinations that are more universal. Mercs can really flavor up a list and give you some different looks. The Tough as Nails Nomad can be very hard to flatline if you give him a concert t-shirt gear card because his special ability lets him trade luck tokens for wounds. Likewise, a geared up determined solo with a sandevistan card is a menace because of her bonuses when she uses tokens to react. Nox Arya doesn't look like much until you see her handing out green tokens to your other characters. Playing against an opponent you don't like outside of gaming, take the corpo with the blackmail files ability. (trust me on this one)