Plus it will stop the monopoly of the UEFA and create some competition.
And based on today's ranking in the national league from UK, Spain & Italy here are the team you could see in CL/EL/ECL.
CL: Sevilla FC, Villareal, Real Betis, Real Sociedad, Leicester, West Ham, Everton, Leeds, Atalanta, Napoli, Lazio and AS Roma.
EL: Grenada, Levante, Aston Villa, Wolverhampton Wanderers, Sassuolo, Hellas Verona, Sampdoria
ECL: Celta Vigo, Crystal Palace and Bologna
And after few years, cause big teams like Real Madrid, Manchester City/United, Barcelona, Inter Milan are not participating in CL/EL, you will see fewer Spanish, Italian and English teams but more french, Portuguese, or Russian teams due to UEFA national league ranking.