What timing/frequency should we use for B2C email marketing after the first contact?

It depends on the source of the leads for the B2C. It is a very personal experience and also depends on the relationship level you have with the clients. I have clients who are very successful with a more moderate approach. We have worked out a pattern where they contact them within 5-7 business days. Their clients will not even talk to them before a minimum of 5 business days.

A solid CRM system will allow your team to work towards finding a good average response time. Personally, and as a business owner, I do not want to hear back even further out. I also believe that it depends on the maturity level of your team. Age and maturity make a difference.

I hope this helps.

Instead of focusing on timing and frequency, you may find it more valuable to consider what content you're sending in your follow-up emails. Are you simply nagging them to call you back? Or are you providing helpful content based on the needs/challenges you uncovered during the initial call? Put yourself in their shoes. What kind of email would you click on or respond to if you were in their position? If you're solely focused on being helpful and not asking anything of them, it won't matter if you send the email 2 days later or 5 days later. (Though I'd argue sooner is better than later, within reason.)

Hope this helps! Let me know if you'd like to discuss further.

Drip and email campaigns typically have optimal results every 3 to 4 weeks to nurture prospects through a sales funnel (direct response campaign management). It is as much the frequency as the content and messages that is provided to help the prospect convert. In some cases, frequency as much as daily is used (groupon), while in other services or products (industrial) monthly frequency is usually sufficient. Monitor your open and conversion rates using applications like Mailchimp to optimize your campaign. Let me know if you need assistance/clarification.