Wordpress site - improvements to stills page

I have a new potential job. On my site there is a page for my stills work: http://www.philipclemo.com/stills/. I think it's using Shadowbox. It's a while since I updated this page and I'd like to do so with a couple of new groups - each with several images in them.

Currently there is a placeholder image for each group and then you click on that and it brings up a viewer where you can view one image at a time in the group. I can't quite remember how I added groups and images to this page before and this is doing my head in. I am now considering options:

1) Is there a better plug-in that will make adding groups/folders and adding images to this page easier?

2) Is there a plug-in that will allow visitors to click on a group and it will open a page showing all the images in the group - then you can click on any individual image to see it larger? - this was my original wish before getting Shadowbox.

3) Is there a plug-in that can show all the placeholder images the same size/ratio - even though the originals may be different ratios - don't mind some cropping.

4) Or should I stick with Shadowbox and get it set up in a way that is more effective and easier for me to use?

Would be good to have some advice on the best way forward.

All the best

Phil