I'm not sure it would really help or hurt at all. There are only a handful of cases where the prerequisites are the onerous part of a PrC, usually it's their crippled casting advances or other useless/detrimental class features that make them bad. If you're keeping the level minimum to prevent early entry, very little will change except a handful of skill points that don't have to be spent, and the skill requirements for PrCs are usually in line with their theme or intended entrant.