Re: 33 combined slams vs 1 - does Murray have the right to be in a "big four"?
But right now he's unquestionably the third best player in the world (with Nadal out) - closer to the second than to the fourth - , so if this 'Big 4' refers to the four best players at the moment, then yes.
MTF games Grand Slam titles:
Suicide Tennis - Wimbledon 2014
Fill-In-The-Draw - US Open 2014
Suicide Tennis - Madrid Masters 2015 and ATP250 Kuala Lumpur 2014; 2 finals lost (Wimbledon 2015, Dubai 2015)
Fill-In-The-Draw - ATP 500 Rotterdam 2013 and ATP 250 Geneva 2015
Tennis-Tipping - Vicenza CH 2014 and Todi CH 2014 (with vn01); 5 finals lost