All-time would be the boring choices of Roger, Marcelo & Rickson for me.

Also for somewhat personal reasons (my instructors are under him) plus he can't be denied when talking about effective grappling in MMA, Demian Maia. All his fights are worth a study.

When I really got into the sport, it was the era of Rafa, Cobrinha & Buchecha, so they inspired me a ton.

Seeing Xande Ribeiro fight live & up close at the ADCC in Finland few years ago made a big impression on me.

I also really like Lucas Lepri. No bomba and been at the top for a long time. Such a precise game.

Lepri is no joke... the guy is amazing.
Maia is def a force to be reckoned with.