Comprehensive Cleanup and Item Respawn originally made by hexef. Please go visit his mod for the original description, and leave him a download and endorsement.

I recommend this mod as well so you can save time and know when to revisit places. The settings you want on are Local Cell Map Respawn Indicator and Unvisited Interior Indicator.

Requires NVSE, JIP LN NVSE Plugin, JohnnyGuitar NVSE, ShowOff xNVSE and the Dead Money, Honest Hearts and Old World Blues DLCs

Personal permission was not attained as he has not replied to his mod. However, I will take this down should he request so in the future.

You are being forewarned, this mod was made aggressive for personal use and may crash your game and ruin your autosave slot should it bug out. It may do so at any time as this game is old and unstable, please take care and save often.
If something bad does happen, don't panic. Load up a previous save and disable the mod then test things out.

Changes I Made:

• Forgive me for forgetting to mention, but the respawn timer has been reset from whatever multiplier to just basic iHoursToRespawnCell flat no modifiers.
• Added 'Rebound' system, which will noticeably cause two loading screens when entering respawned interior cells which means. . . THIS MOD IS NOT RECOMMENDED FOR LOW END PCS. It causes you to temporarily teleport to a 'safe cell' (your last home cell) and back. This is due to this mod marking items for delete to respawn them, fallout then has to go through two load cycles to respawn them. The first finalizes the despawn. The second forces the respawn. Unfortunately, this means there is no reliable way to force exterior cells to respawn immediately, you will always have to do two runs through any high value exterior areas to get them to respawn, or if you can find the load point for the cell and run around the area a little bit before fully entering the cell, that could work.
• Added system that respawns cells immediately after downloading the mod, is aggressive and uses missing item counts to respawn every cell you've visited no matter how long it's been, therefore. . . I RECOMMEND DOWNLOADING THIS AFTER YOU'VE VISITED A GOOD PORTION OF THE MAP AND ARE PLANNING TO EXPLORE A NEW AREA BUT. . . This shouldn't be that big of an issue if you don't mind the loading screen flash, all it would do is just reset everything to normal anyways.
• Remove randomness from respawns, everything will respawn, except unique items.
• Fixed potential quest objects (containers, terminals, doors) being locked when they were unlocked outside of the players control( big MT doors, etc.), potentially causing a soft lock. Side effect is some terminal locked doors will not relock when they obviously should.
• Resets all non-quest doors to their original positions.
• Removed weird code that empties revisited cells that have yet to respawn???