I think jewelry as gifts for bridesmaids & flower girls is a fabulous idea. If you buy carefully then it can be something that they wear often - a token of your love & gratitude & a little piece of your wedding too!
I think that perhaps it's a rare thing that there will be a 'one fits all' gift, but gifts that are different but in the same vein can sometimes address that.
Anyway, here's a very small selection of trinkets to inspire you.
As well as possible gifts the crystal earrings, studs & diamond bangles could easily be worn as bridal jewelry, possibly even the lotus or bubble necklaces for a more contemporary bride.
via daniel m jewelry/ lulieyal/ lulieyal
via annekiel/ annekiel/ virine
via metalicious/ artisan look/ PSodhi/ PSodhi
The studs or bangles could also work well as a gift for flower girls that will easily transition through the years with them but for something less precious, these tiny initial necklaces could work especially well as most children love to see their name on their belongings!
And if you're looking for something a little more 'now' for the little ones, I'm sure these cute pieces would be very well received...
via esmeweatherwax/ esmeweatherwax/ esmeweatherwax