I recently had a question like this (Lilligant, Serperior, or both?), so I'll tell you what I got from the answer to my question. My friend, MoonlitMadness, told me to keep my Serperior, and not my Lilligant. But, what happened then was I realized I wanted to keep my future Lilligant a little more than my future Serperior, and I knew that if I passed the option to get a Lilligant up, I would feel bad. So, by that answer, I realized what I wanted. You may want a Pansage a little more than a Minccino or a Minccino a little more than a Pansage. If you realize that you do, take the one that you feel that you want more.
If you want to hear my opinion, I like Minccino more than Pansage.
Let's look at Minccino's and Pansage's evolutions to see what's better:
Cinccinos' Base stats:
Okay HP: 75
Good Attack: 95
Okay Defense: 60
Okay Special Attack: 65
Okay Special Defense: 60
Great Speed: 115
Cinccino's Weaknesses and Resistances:
Weak to Fighting
Ghost doesn't hit it at all
Simisage's Base Stats:
Okay HP: 75
Good Attack: 98
Okay Defense: 63
Good Special Attack: 98
Okay Special Defense: 63
Great Speed: 101
Simisage's Weaknesses and Resistances:
Weak to Fire, Ice, Poison, Flying, and Bug types
Resistant to Water, Electric, Grass, and Ground types
So, if you're looking more for the base stats, Pansage is the one you should take, but if you're looking more for weaknesses and resistances, I would suggest Minccino. It's only weak to Fighting type, and Ghost can't hit it!
But, all in all, it's really your opinion on which one you should take. If you were asking me, I would take Minccino, hands down, because I like it's design better. But, like I said, it's your team, so you can do whatever you want.
I hope this helped! :)