Weddingbee boards

I think the long dress will be just fine! Especially if your FI is wearing a suit and the groomsmen are wearing ties. Go for it! Always better to be overdressed than underdressed! And who cares anyway...you're the bride! :)

I think a lot can depend on the dress. Do you have a picture or link you could share?

A long, lightweight dress in a more casual material like cotton can be perfectly informal, while a floor length satin number encrusted in jewels might be more suited for the red carpet than a rehearsal dinner. :) 

I think that's beautiful, and it's perfectly appropriate for a restaurant where your groom is in a suit! The jersey-ish material keeps it from being too formal or too casual. I say go fo it!