I was almost done with the game 8 years ago after doing all the overland stuff and maxing crafting in just a few months
Then I did something I never tried before. I joined a role playing guild because i enjoy the game setting. I’m still RPing with a couple characters in a collaboration with a couple of guilds, in addition to getting into the end-game content
Already tried fishing? I can recommend that, if you're after some relaxing low-effort activity.
Otherwise there are enough dailies also for solo players I think. You could farm some motifs for example and then play around with the outfit system.
Finally you could start over with another toon and experience the journey again.
If you've done all that, there isn't much left. Except housing of course.
Never get between a cat and it's candy!
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Overland difficulty scaling is desperately needed. 9 years. 6 paid expansions. 24 DLCs. 40 game changing updates including One Tamriel, an overhaul of the game including a permanent CP160 gear cap and ridiculous power creep thereafter. I'm sick and tired of hearing about Cadwell Silver & Gold as a "you think you do but you don't" - tier deflection to any criticism regarding the lack of overland difficulty in the game. I'm bored of dungeons, I'm bored of trials; make a personal difficulty slider for overland. It's not that hard.