What plugins would you recommend for my bukkit minecraft server?

"Also, a plugin that let's you make more interactive structures would be nice. For example, I was on a server where a lever could trigger the spawning of blocks or mobs, and a bunch more stuff could be done with redstone "

= You can apply this with a plugin titled, CraftBook 'http://dev.bukkit.org/bukkit-plugins/craftbook/'

And maybe also a plugin that can do permissions and a ranking system.

= I would recommend PeX "PermissionEX", as it is very easy to use rather than GroupManager in my opinion. 'http://dev.bukkit.org/bukkit-plugins/permissionsex/'

I want a certain section of my server to be survival only, and have certain parts where users can't destroy blocks.

=This can be done by using 'Faction' plugin which is easy to use, if you want to make a non-grief & anti-monsters area or a pvp-enabled but non-grief area. 'http://dev.bukkit.org/bukkit-plugins/factions/' (I recommend for a lower version of 'Faction' plugin as it doesn't need any 'Core' plugins. Don't worry! It works for 1.7+

= WorldGuard also do the job! If your up to some reading the plugin, you can, WorldGuard is a big plugin, and you can do a variety of stuff with it! 'http://dev.bukkit.org/bukkit-plugins/worldguard/'

*I would recommend some RPG plugins such as Mythic Drops and more, it will really increase your survival experiences!