You clearly have no clue what you are talking about, just in my circle of friends / guild members there's like 4-5 of them spending every month from 40 to 120€ to get gold, obviously they don't do it from F9 because they get it 3x cheaper with other methods.
EDIT : point by point,
1st) HR wasn't really crowded by whales the way you understand them as whales, it was crowded with geared players, most of them f2p, aka smart players, then there was a portion of pay2win ppl but they were not the majority.
2nd) Whales do not lose their time in doing an event, they just throw a lot of money everytime there's a decent deal in f10 and that's it
3rd) The NPC buying gold is the most stupid idea I've ever heard, no offense but that doesn't help.
4th) Abolish HMCoin is another stupid idea, they make this so f2p has something with really low chance and amount but at least has something, instead of your idea I'd rather say abolish F9 and make every item in shop to be tradable via marketplace, this way spenders do compete to sell cheaper instead of f2p (majority of users) competing to see who devaluates the gold faster. At this point it can't go under 1:1 anymore but still 1k gold is 3.5-4.5€ on a player to player transaction and that's the issue here, in other MMO you can buy gold too but there's a culture of buying stuff in shop and sell it on market to make fast gold and safe, that's what we're lacking in this game.