Being evil gives you easy karmic streaks that are used for a lot of the fights and for other reasons I can't think of at the moment. As for the shards, yea, there is a specific route (minus one part, i always choose different paths while you are waiting for the dialogue to end when you start Quid Pro Quo) I want to say I get about ~40 ish shards but I haven't counted in a long time (when shards weren't as optimized for me). I might even get around 50-60 shards lol
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