New wordpress website: Jewish historical database

Hello,

For a friend of mine I’m about to set up a new website with a database of Jews in hiding during the second world war in the Netherlands.

The website should provide information on places and family names, with indexes. I’m also looking for a good related search plugin, when people search a family name, related families or places show up in a nice visual way.

I’m thinking of setting this site up with an index plugin and ultimate search, besides setting up some custom post types.

The database on the current site (which is extremely user unfriendly) is already huge, so I’m looking for input on setting this up the best way.
I also appreciate input on a lovely, workeable theme that will display the people’s database in a nice way.

I’m not a novice on wordpress, but there’s no money and time to build a theme from scratch.

Thanks!