[SKSE and mods function?]

Sorry, yes you have to load it up manually.

But once you have SKSE, you can go to the dashboard on Vortex and you'll see "skyrim script extender" button.

Hit the three little dots next to it ans select "make primary". Now any time you launch the game through Vortex

it automatically launches with SKSE.

[SKSE and mods function?]

SKSE should automatically load itself when you start the game. Mod installation works like any other mod (no additional steps due to SKSE).

[unlimited adoptions?]

Improved Adoptions + Hearthfire Multiple adoptions seems the way to go.

[Remove invisible light sources]

There is a mod for Oblivion called Weather All Natural which replaced all (or almost all) of the invisible lights with real ones like torches.

[Remove invisible light sources]

I wonder if it's possible to remove all of the invisible light sources in Skyrim. Some mods, like Climates of Tamriel try to fix the overly bright nights by (I think) dimming down everything. I honestly tried even the lowest possible settings, but it's still too bright. I think ELFX does this, but only for dungeons and interiors, it doesn't seem to fix the "nighttime". Thanks.