Hi!! Without the ties, you won't be able to tighten at the waistline, so the dress will have a loose, more relaxed silhouette. I personally like both versions, but it's up to your preference 😉
Hi! You will need to create the lining to insert foam cups for this dress. Alternatively, you can try a strapless bra or an adhesive bra. Here, I'm wearing a strapless one, and it looks perfectly fine ;)