Hey, we all have our favorite fighters for one reason or another. Nothing wrong with rooting for them.
I have to agree with you, there's nothing wrong with rooting for our favorite fighters and certainly nothing wrong with rooting for JMM. Marquez is one of my favorite fighters, I picked and rooted for him in most of his fights, except of course... against Pac. I considered JMM as Pac's equal and even better in terms of skills when both of them were fighting at 126-130 lbs but they are miles apart now as Pac had successfully moved to WW while JMM had maxed out at LW, apparently. I don't think JMM would be competitive and probably would be KOd the next time unless he could pursuade Pac to meet him at LW limit.