Why can't I find a job to main?

[Shikiseki]

The thing about leveling new jobs at this point in the game's lifespan is that jobs really don't unfold until usually very late in the game as skills get pruned and spaced out to make space for shiny new attacks every expansion, leaving inbetween leveling very stale for some jobs (for example the highly praised reaper absolutely sucks below 80 and really only feels complete at 90).

I know that leveling jobs is actually half of the game in a sense but I'd focus on the following aspects when it comes to find a RP main:
- your weapon choice
- your party role and teamplay
- the overall aesthetic of the attacks and vibe of the job

stuff like shutting down jobs because they wouldn't make sense lorewise (excluding Dragoon and Summoner) would be a shame cause there are always ways to circumvent that (i.e. calling yourself an Evoker instead of Summoner as the reflection version of the Summoner which was founded by the allag - don't forget who founded them in the first place, I'm sure there are ways to make it interesting )

tl;dr - you might like Summoner on regardless due to minimal buffing and mostly focus on direct damage or Black Mage if you don't mind the long cast times

[einschwartz]

The thing about leveling new jobs at this point in the game's lifespan is that jobs really don't unfold until usually very late in the game as skills get pruned and spaced out to make space for shiny new attacks every expansion, leaving inbetween leveling very stale for some jobs (for example the highly praised reaper absolutely sucks below 80 and really only feels complete at 90).

This.
I would suggest keep playing the ones that interest you the most. Or switch between 2 or 3 of them.
Based on your post, I feel like you already gravitate towards SAM and RPR, so maining those two jobs while progressing with MSQ seems like the best option.