There is no preconceived magic number of attendants . Choose attendants you trust with your life, your cash, and your feelings. Surround yourself with people who are up to the challenge so you won’t feel guilty asking them to tie bows on 200 favor boxes or go on numerous dress shopping excursions. The bridal party is also responsible for purchasing dresses, renting tuxes, throwing a shower, planning the bachelor and bachelorette parties and numerous other duties (i.e. keep their expenses in mind). Remember that the bride and groom are responsible for bouquets, boutonnieres, and gifts for all attendants. If you’re on a tight budget, keep your wedding party small. If you really can’t decide, try this ratio: one attendant each for every 25 guests.
There is absolutely no reason why you need to have a matching number of attendants on each side. You are choosing these family members and friends for an important role. You don’t need to include 2 random co-workers just to make each side even.
Does the bride have a say on who the groom chooses? Not really. The groom needs to choose who he wants to stand beside him on the wedding day. As a bride, you wouldn’t want your mom or fiance dictating who you choose for bridesmaids. Of course, the groom should talk to you about his choices but the final decision is his.