A Tiagra triple crank is another way to go. There’s not a big difference in quality between Tiagra and 105, and the triple can be set up as 26/39/50 to give a really wide range, especially when paired with an 11-34 cassette. I’ve heard of folks even using a 24 small ring, but haven’t tried it myself. I use the 26/39/50 and it works fine even though I think it’s technically out of spec for the derailleur.