] On beginning the book, I always thought Elinor would make a good match for him. His quiet strength matches hers.

I heartily agree. I want to shake both of them for each longing after someone who has not indicated that the feeling is mutual, when they are both so suited for each other - both have good sense, maturity, and they can actually talk to one another, as shown in ch 12:

"In Colonel Brandon alone, of all her new acquaintance, did Elinor find a person who could in any degree claim the respect of abilities, excite the interest of friendship, or give pleasure as a companion. ... [I]n conversing with Elinor, [CB] found the greatest consolation for the total indifference of her sister."