The EF24-105 should be removed from the L line. It's mediocre at best. So if you can tolerate it's weaknesses, it should suit you fine. Or, if 105 is not important, but IQ is, I'd recommend getting the 24-70 F4 or 2.8L II.
I don't agree. The 24-105 is very well built, definitely "L" quality, auto focuses quickly and quietly and is pretty good optically. The 24-105mm range is provides an extra 50% of reach over the standard 24-70 zooms. Its also a terrific bargain at around $600 on the used market. Excellent quality for that price!
There are of course better standard zooms, but they all cost more money, so the consumer has choices. I owned one of these lenses for two years and was very pleased with the images I captured with it. I replaced it with a 24-70 2.8 II last year, but if I didn't have the funds available I would still be using it.
Not all L's are excellent optically, some are just good. Personally, I like having options within the L designation.