MEPs get elected with proportional representation on closed lists in a nation-wide single district.
Emailing 60 of them from an array of different parties with no official stance on the issue and no more of a direct relationship with you than with millions of other people is less direct political action and more spam. Pretty sure collective action would have a better chance.
Well, the EU has a consultation period on new regulations, but I don't know if that's open for this specifically.
Generally, I would say organizations on each country are often the ones with the infrastructure in place to issue a recommendation on these things. Consumer support orgs, unions, privacy groups and so on. Political parties if your country has one with a definite stance on the issue. If you can get those involved and they can get the press involved now you have an avenue for mainstream awareness, which frankly is more likely to do something than a purely online-driven signature or email campaign.
The rest may differ per country and even per party. It depends on what participation mechanisms you can deploy for each.
To be clear, I'm not against also reaching out to MEPs, but given how in many places they act as a collective blob representing national partisan interests and how electorally they don't have a particular incentive to engage with individual voters I don't know that it'd work best in isolation. I'm not particularly against that, either. "Contact your representative" is a staple of small district, majoritarian, first-past-the-post nonsense and I have no particular desire to move in that direction. I'm way more comfortable with a party-heavy system than with that weirdness.