I think the dresses are fine but not amazing, I wouldn't pay that for synthetic fabrics. I would keep an eye out all summer, unless you see something that you really love I wouldn't rush. I would keep an eye out and wait for whatever I like to go on the sale.
I would wear whatever your style is, sod the Mother of the Bride traditional look.
Personally I love Monsoon dresses and if my daughters got married I would be floating around in a big floral number. If I was more comfortable in trousers I would wear trousers.