What if some tempting rewards were offered for achieving lower ranks: bronze, silver, gold? Those who progress beyond those ranks would get their plates from platinum, diamond and crystal plus the rewards for getting through lower ranks but those who would just want to get the actual rewards (whatever people would like most, I guess mounts?) only need to play through lower tiers which would be comparable to casual and might encourage players to go further.

I am strongly against enhancing rewards for top tiers.