Canon makes excellent lenses for APS-C DSLRs.
17-55, 10-22, 15-85, 60/2.8 Macro ... all good and optically fully "L-worthy". Price is right too, if purchased using cash-back/special offers. The 17-55 IS is on of the main reasons I never switched to Nikon in the past.
10-18, 55-250 STM, 18-55 STM ... very good and very decently priced (if not "dirt cheap"). Rella good IQ, excellent price/value.
Yes, those are all excellent lenses ... but apart from the macro, all of them are also zoom lenses with rotten apertures.
Primes? yes ... 40/2.8 pancake. Dirt cheap, and optically fully "L-worthy". Oh, it can even do FF? The better!
Semi-true ... the 40mm flapjack lens isn't really very suited on a "crop-frame" camera for the same job it would have shined at on a "full-frame" camera if the latter cameras weren't so darned big, i.e. discretion.
Something mising? Not really.
An EF-S 35mm f/1.8 lens that actually takes advantage of the ability to be deeply recessed into the camera.
Tele lenses are same size irrespective of APS-C or FF image circle ... only dependent on focal length and f-stop, so no point to make or purchase APS-C tele lenses.
Other than that .. I would buy an optically great & very compact 16mm/4.0 pancake for landscape.
You can't, because Canon doesn't make it.
The last thing I would ever buy would be EF-S "L" primes ... say something like a Fujinon 56/1.2 @ 1000 USD/Euro ... never ever. I don't spend a grand on FF prime lenses.
That FUJIFILM 56mm is the next lens on my purchase list. To me, spending a "grand" on something that I'll use for the next eight to twelve years is good economy.