My first favorite who mixed different arts was Bruce Lee, not only did he punch and kick, he also did some grappling moves on Samo Hung in Enter the Dragon.
This was in the 70s. Hmmm, He is not using regular Kung Fu like many other contemporaries, very interesting i thought.
I got hooked to MA in the 70s and 80s(mainly due to Bruce) and started mixing arts myself and started training Wing Tsun for handtechniques and Tae Kwon Do for kickingtechniques.
Then i got hooked on Muay Thai , Wushu and Xin Na lil later in the 80s
During the K-1 era my favorites were Crocop (damn, that guy could really kick!) and Andy Hug, honorable mention Glaube Freitosa with the Questionmark Kick
Then when UFC and Pancrase arrived to my attention in the 90s, my first fighters i became a fan of were actually the Shamrocks. Oh and Pat Smith demolishing "Ninja" Scott Morris face made me re-evaluate my training in Ninjutsu as well
How easily Frank Shamrock neutralized the aggressive Kevin Jackson, how Ken (and Bas Rutten) fought in Pancrase.
Then later on i became a fan of Sakuraba, Enson Inoue and Igor Vov in the late 90s.
In 99 i think Wanderlei arrived to the Pride-scene and i followed all his fights.
Too many to mention, but a good summary would be in this order, Bruce Lee, Samarth Pakartmoon, Andy Hug, Crocop, Glaube, The Shamrocks, Bas Rutten, Enson, Igor, Sakuraba, Wand