1) Drop the "everyone must agree to make changes" idea that people here like to peddle, and do it loudly, so everyone in the community is correctly informed
There never was a rule that soft-forks require total consensus. It is desirable but not mandatory.
A majority of miners can inherently implement a soft fork against the wishes of the rest of the users.
Merchant/exchange/user checkpointing is the defense and therefore is a perfectly valid response to miners taking such an action. If a soft fork is opposed by a large section of the users, then threatening (and implementing) a checkpoint is the correct response.
No group can force through a hard fork, it inherently requires buy-in from a large portion of the userbase. That is where the "total consensus" requirement comes from. Naturally, absolute total consensus isn't actually required but you do need very large consensus and also consensus across the various sub-groups.