We had something called bonus point for chasing total within certain overs, winning match with certain numbers of over to spare. May be we can reintroduce that.
NRR is good, it's consistent and gives equal chance to all teams. It also fixes rain issue. Also no dead rubbers and boring matches, teams will play with all their might.
But it is, in a low scoring match Victory margins can't be huge but in a high scoring match the victory margin can be quite large. There are plenty of other sports where tie breakers are decided on Head to Head comparison first before other things are considered.
ICC needs to correct this flaw.