Also Alchemy farming instead of cash shop buying will be stopped.
This is very wrong. Alchemy farming did not insert any gold into the economy, it just moved gold from cash shoppers' hands into farmers'.
Unless they either bring mob gold/gray items drop rate to what it was before or make any of the demanded resources obtainable from Negotiants possible to sell on the regular AH, pure f2p players will start leaving or resorting to move abusive methods just to "stay alive".
Only thing this can cause is a plague of green geared 211 111 rune alts queuing everything that can bring gold. Baaaaad move.