One moment my friend, maybe you missunderstand one point - the Top-3-bonus won't be taken completely away, he will (when the proposal is successfull) only removed for Crowns and Merrits but he should stay for the SPS-rewards.
So the proposal won't change anything in the top-3-bonus regarding SPS (at least if 10 or more guilds are in the Tier - not the brawl - ).
To take away the reward reduction for Tiers with less than 10 guilds seems very logical - this will probably only apply for Tier 5 - but why guilds who invested in the store can enjoy the merrit bonus but guilds who invested in the arena will be cutted down be the reward reduction factor.
This factor was usefull to prevent that the first guild who reach Tier 5 will win a very huge amount of merrits but now it has lost his sense as it was enogh time to bring Arena to Level 9 (I mean for the top-10-guilds)