That would definitely be cool. Something else would be allowing teams to carry over previous years kits as long as the sponsors and manufacturers don't change. Like Barcelona could have kept their Senyera kit from last years game for this year (they actually did wear it this season) or next year when they wear the hoop kit they can keep this years "traditional" design as an option. But a club like Man United going from Nike to Adidas (or the sponsor change this season) wouldn't keep their old kits since its more of a major change.