Figuring things out, need wedding ceremony advice

So looks like we are gonna have a mini wedding first with just parents, siblings, and grandparents. Still gonna be about 20 something people but it will be the official one so my fiancé’s grandma can see us actually get married. My only issue is his family is Very religious, I am not. Well... I’m pagan and I plan on having pagan practices in my big wedding(which we are doing later so we can have more family and our friends.) I’m not sure what to incorporate into the small one to appease the grandparents that will be at the mini wedding or if I should just ask for a very super simple religious sounding wedding but with no direct quotes and such. If that’s possible?
Im not sure. My parents are not religious and didn’t make us go to any churches or anything like that. So I don’t even know where to start. My fiancé grew up Mormon but doesn’t practice that and actually is pagan with me(though our separate practices are also different lol.)
i have friends of multiple religions and though I know basic stuff for most religious I’m not sure how far his family is determined to see their practice in my wedding with out it causing issues...
i know it’s our wedding and we have the final say but I don’t want my fiancé to have issues with his family because my want for a non religious wedding before Our big Main wedding(personally feel is our actual even though legal would be the small one.)