Uh... All three of the above? Lol.
There's something special about all three of them.
I would like to travel alone only for short times. But for almost all the other times, I would like travelling with a partner or a group.
For groups, I would prefer the groups to be small, with no more than three other people other than me.
Of course I would love it if my Pokemon could talk like humans, and I would never keep them inside their Pokeballs anyways, unless needed. They would just increase the fun.
The reason I'm confused between choosing a group or a partner is that, while you travel with a group, it doesn't get boring. The more the better.
But while you travel with only one other person, it allows a lot more social bonding to occur, and greater levels of character development too, if you know what I mean.
But my final decision is travelling in groups anyways. Big groups like 10 people would really cut out the communication and social bonding between each person in the group, and so I prefer a small group instead.