Opinions: Which liquor for signature drink at wedding?

White rum or tequila for this drink?

Our venue offers this signature cocktail: white rum, lime, coconut cream, coconut water, sprite. However, we and our guests are more of tequila drinkers. Would this be good with tequila instead of rum?

Also, I’ve had a delicious coconut margarita that included tequila, coconut rum, triple sec, lime, and agave, so I’m wondering if this will taste anything similar.

Our other signature drink will be an old fashioned.

Thank you in advance!