Friend Getting Married - What Type of Celebration?

If it is limited to this grouping, sounds like it is, then I would think that a nice luncheon would be appropriate or an after noon tea at one of those fancy tea houses or something like that. I would not make a huge fuss over it all maybe you as a group get together to give a substantial gift off the registry as a group and present it there. Either way I would do a day/early evening event, low key, no pressure and keep it along the lines of what your group does anyway.

Absolutely have a bridal luncheon! How fun! A friend of mine recently re-married (her second marriage, his second marriage). We took her out to "girls" dinner at a nice restaurant and celebrated her happiness.

I think a bridal luncheon with your lil' group sounds amazing!

I would do a bridal luncheon at a nice restaurant!
How nice of you.
The restaurant does not have to be expnsive just nice and a step up from
the super-casual, walk up & order kind.

Does your friend have any particular interests or charities that she donates to (could be anything from a missionary that your church supports, or a group within your church, or volunteering with some organization, or maybe she is passionate about preventing animal cruelty, for example)? Maybe you could take her out for a nice celebratory dinner and present her with a card saying a donation in her name to her favorite cause has been made by all you friends, in lieu of traditional gifts. That would show her how special she is to you but would allow you to skip the gifts that a new young bride just starting out would need.

Talk to her and tell her you would like to celebrate her upcoming marriage and what you would like to do. Ask her if she is open to it.

2nd marriages should still be celebrated in my opinion!! I think it's great of you to want to do something for her!!

I would do a luncheon at a nice restaurant or a pot luck at the church. Whichever you feel will be more comfortable, etc. for everyone!!