I only use mons I like, too, even when battling competitively, and usually manage to hold my own - even if I only have one mon in the tier I'm forced to battle in. I hate how tiers are done. I just wish everyone would use mons they liked instead of the most powerful ones they have. When I was battling as a kid, the only rules I'd have would be like "no legendaries" or just one or whatever because they were too powerful to have a full team of. But then people had to go and decide on tiers of power. I don't like that. Now that they're ranked, the only people that are fun to play with are the ones who don't know what's in what tier or what the tiers are, and are willing to submit to the "no legendaries" rule.
"The point of war is not to die for your country. It's to make the enemy die for his."