MailChimp / SendInBlue newsletter template update needed

We have an existing MailChimp template we've been using for a long time for our company newsletter but now need to update it. We're having a problem with the RSS feeds from our WordPress site feeding dynamically into the newsletter as well as needing to update some other items.

We are potentially also looking at SendInBlue as an alternative to MailChimp, so we need someone who understands each platform and its capabilities.

Need someone who knows about these platforms:
WordPress
MailChimp
SendInBlue
API in general
RSS

We will be asking lots of questions, looking for recommendations, needing advice etc so it is important that someone applies with knowledge and confidence of the subject matter. Good communication and ability to troubleshoot problems is essential.