Cyberpunk 2077 – Are There Drawbacks from Using Drop Points?

There are numerous missions (both story and side missions) that want you to go in silently and not kill anybody. These missions can still be completed loud but may have a different outcome - in the instances of side jobs this normally means you're missing out on a bonus payment for completing the job how the fixer wanted it fixing.

There are also numerous instances where killing somebody is then bought up later in conversation (as both a positive and a negative, depending on the conversation you're having) however this does not have a final impact on the endings available to you.

There is no reason to only do gigs for only one fixer. There is sort of a reputation with the fixer, but it isn't negatively affected by doing gigs for other fixers. This may not hold true for the main storyline. I would recommend completing as many gigs as possible unless you are speedrunning.