New here: just a question regarding flash setup.

I just bought a Yongnuo YN600EX-RT flash. I would like to have a two off-camera flash setup. So my question is, should I just go ahead and buy two more 600EX-RT flashes, and use one on camera as master and two as slaves, or should I buy one more flash and a YN-E3-RT trigger?

Is there any advantage to the trigger setup over an all-flash setup? Since there is only a $50 difference between the trigger and flash, I am leaning towards the three-flash setup. Will I lose some functionality if I go that route?