I'm wondering, which of the three DLC has the biggest impact on the overall game performance?
-Dawnguard adds some exteriors to the original map, which I think should drop the overall game performance quite a bit.
Many new creatures were added which can also spawn in vanilla dungeons.
The new features (the ships, vampire attacks in towns, arrow crafting, the perk trees) shouldn't help either.
-Hearthfire adds clay deposits and stone quarries to the original map which could cause performance issues. It also fills the general good vendor chests
with many useless junk which could increase loading times in certain areas.
-Dragonborn does not add any noticeable changes to the original map. Instead, it uses it's own map. I'm not sure if this has an impact on the game
performance outside of Solstheim. Most of the DLC-added creatures only appear on Solstheim (except Hulking Draugr, but they are quite rare).
It adds a few weapon and armor sets, but seem to only appear on Solstheim (and its vendors), with the exception of Cultist Robes and Nordic Carved armor, which can be found on high level bandits in the main game after installing the DLC.
So, my guess would be Dawnguard > Hearthfire > Dragonborn, because Dawnguard seems to add the most stuff which could drop the performance and most of the stuff from Dragonborn can only impact the performance when actually being on Solstheim. Hearthfire could have an bigger impact on the game performance due to adding mines to both interiors and exteriors and adding a fair amount of backround scripts per finished house.
What are your views and experiences on that matter?