Coming back to records up to 3 Dec 2019:
A total of 334 players have captained in Tests. Here are those who have captained in the most, along with their win/loss/draw records:
Kohli is now 12th on this list, somewhat ahead of Root and Steve Smith. He needs 8 more Tests to overtake Dhoni (besides other recent captains such as Cook and Misbah).
Some simple parameters for ranking include the percentage of wins and the win/loss ratio.
We consider these for the 157 who were captains in at least 10 Tests.
Ranked by percentage of wins:
Headed by Australia’s “Big Ship” Warwick Armstrong, who led the team to successive 5-0 and 3-0 Ashes wins after the Great War. Virat Kohli is 4th, after Steve Waugh and Don Bradman. Other current or near-current captains here are Kane Williamson (#12), Faf du Plessis (#18), SPD Smith (#19) and Joe Root (#30). The next from India is Dhoni (#40) and 45.00%.
At the very bottom are M Ashraful (13 Tests and no wins) along with Ian Botham (!) and Khaled Mashud (12 Tests and no wins). Just above them are SA’s Alan Melville and Zimbabwe’s Tatenda Taibu (10 winless Tests).
We can also look at the ranking by Win-Loss Ratio for the same set of 157 captains:
Note that Armstrong has 8 wins and 2 draws with no losses, and thus has an undefined win-loss ratio. Everyone else with at least 10 Tests has at least one loss, starting with the second-ranked Douglas Jardine (born in Bombay).
Kohli is 9th here, ahead of all other contemporaries. Next is Williamson (#18), GC Smith (#33) and SPD Smith (#35). The next from India is Ganguly (#42) and 1.62
At the bottom are the same quintet listed above, with Ashraful logically at the bottom with 0 wins in 13 Tests followed by Botham and the others.
Among those who captained in less than 10 Tests, a notable performance was that of England’s Brian Close (7 Tests, 6 wins and 1 draw).