It is in my opinion a silly notion that you cannot use your favourites simply because tiers exist. On the contrary, tiers actually facilitate people who want to use their favourites by relegating pokemon that are too powerful for them to the higher tiers. This problem, I think, has to do with the mindset of most competitive battlers that OU is the only "real" tier where serious battles may exist, and that some of them get offended when their favourites do not make it into the tier.
It is therefore, in my opinion, a better solution to simply pack up and move to the tier where most of your favourites reside, and be the best within that tier where your favourites can shine without the threat of overpowering top-tier pokemon from the tiers above.