What are some mods that add fun to the game rather then just over powered weapons and armor?
You might want to consider something like FWE or Arwen's Realism Tweaks. Both change the game in ways that make it much more challenging. Also get CevSteel's DC Interiors mod, it will give you a bunch more building interiors you can explore.
Here's the link to the DC Interiors thread:
http://www.gamesas.com/index.php?/topic/1104284-dc-interiors-project-dupont-circle-and-the-waste-land-edition/
Here's the one for FWE:
http://www.gamesas.com/index.php?/topic/1105958-relz-fwe-fo3-wanderers-edition-41/
Also look into Savage Wasteland- Unfound loot. It randomizes most of the hand placed items in the game so you can never be sure what you'll come across. The only things he hasn't done yet is the weapon component items and the general clutter, though he's planning to. He's also thinking about randomizing the locations of the Bobbleheads and Skill Books. Here's the thread for that one:
http://www.gamesas.com/index.php?/topic/1106005-wiprel-savage-wasteland-20/
Last but not least, here's the link to Arwen's tweak's:
http://www.gamesas.com/index.php?/topic/1104662-relz-arwens-realism-tweaks-thread-no9/
FWE and Arwen's Tweaks aren't fully compatible and do many of the same things as each other so you'd need to choose which one you'd prefer, but not both.
Make it so you can only carry 10 Stimpaks, 150 rounds of 5.56 and 2 bottles of water, for example.
Another good option along those lines is using a mod that adds weight to ammo and meds. That forces you to think about how much you're carrying around with you.