Perhaps you missed some of my earlier points. I agree with pegging election deposit to a ratio against MP allowance and responsibility. I suggested lowering everything, lower election deposit, MP allowance and depoliticise town council maintenance and upgrading affairs.
I also suggested a wider and more truly proportionate representation system of the GRC system. The winning team can't be getting all 5 seats if they only win by a whisker. The losing team can't be losing all 5 seats if they lose only by a whisker. This is imperfectly compensated by the NCMP scheme, which I understand is to expanded. I think that's not enough. More needs to done, addressed and balanced. If you get 40% of the votes in a 5-seater, you have 2 seats, not nothing, then become NCMP. If you get 60% of the votes, you should have 3 seats, not all.
By the way, your idea of a designated minority SMC, where got Malay kampung or Indian kampung clusters nowadays? All are Chinese majorities, even for Geylang Serai and Little India in terms of resident voters. It's only a matter of how high or how low is the minority.