Takeshi Kovacs takes many forms based on the sleeve he inhabits at any given moment. That means he could be anyone, with almost any abilities. Over the course of the books and series, he has a few different sleevers as explained below (only the most important):
Ryker's Sleeve (Joel Kinnaman) - This is the most well-known sleeve Takeshi has taken. Elias Ryker's sleeve has a minor combat augment (adrenaline) and an addiction to nicotine that has Tak smoking, despite his hatred for cigarettes.
Wedge Sleeve (Anthony Mackie) - This is the sleeve from the second season of the Netflix series. It's a combat sleeve with several enhancements and a loyalty to the leader of the Wedge that prevents him from harming the leader.
Wedge Sleeve “Prime” (Will Lee Yun) - Equivalent sleeve to the above, but takes the form of Takeshi when he was younger (and taken in by Quellcrist Falconer). Outlives the original Takeshi, so is missing some memories as he was spun up by the Wedge to counter the original.
Because Takeshi can take any sleeve, it's possible for any faceclaim to be used, along with any specification for the body. It's possible for him to take any form in cyberspace, completely separated from the physical presence. Suggestions for faceclaims include the following:
Tahmoh Penikett
Michael Fassbender
Adam Driver