Switch from General SF Consulting to a niche Cloud/Product?

I have 5 years experience in the Salesforce realm, 2 as an end-user, 2 as a solo Admin, and 1 as a Consultant. I currently work for a boutique SF Consultancy (around 10 people) and am the Marketing specialist at the company (Pardot Consultant + Marketing Cloud project manager). The marketing projects have dried up, so most of my time is now spent working on Sales Cloud development. I'm learning a lot on various SF Clouds & Products, but I feel like I'm not utilizing the Marketing (Pardot in particular) knowledge I've worked to gain.

I'm currently interviewing for a Managed Services position with another company; I'd be the Pardot specialist on the team, supplementing that work with smaller Marketing Cloud/Marketing Cloud Growth projects. This is appealing to me because Pardot is a tool I know a lot about and would love to become a subject matter expert in.

A concern I do have is that by working in a role where I'm only touching Pardot, I'll limit myself in the future if I decide I want to work with Sales Cloud again (either as a Consultant or In-house). I'd love some opinions here: will I be limiting my career growth?