Best crm for marketing automation (new lead/intro email) and email campaigns

I’m sure this gets asked a lot here!

I have 13,000 (and growing) leads that I want to create campaigns for from time to Time. I also want to create automations every time a new contact is created (so send an email, wait a few weeks and then send a new one).

Hubspot I know can do this but its price is too high to justify based on how many contacts I have (as is mailchimp). I’ve looked at sendinblue, engagebay and so many other tools out there.

Wondering is theres any that anyone has a working practice with that fots my needs.