Solo/Single Player content.

[Jinko]

Caravan is what you are looking for, if you are on and nobody in your LS is on, go to a Caravan escort and team up with other people.

It's not solo but it allows you to do content if you are on your own.

[Felis]

Additionally, you could work towards a relic, this would actually give a person lots to do solo if you are determined to create your own instead of buying it off the market.

But the relict quest is not very PUG friendly. For the 17 min speedrun and Ifrit extreme you need a team who play well together.
Of course, you can farm some stuff solo and do some quest steps with a PUG. but to finish the quest you need a good team.

[Andrien]

i hear there will be alot of questing+adventuring to do in 2.0